Topped with a sweet cinnamon buttercream, this 8 ingredient oat flour cake is just like a slice of heaven. The fluffy, tender texture and moist crumb will have everyone begging for seconds. Since it doesn’t contain any gluten or dairy, this cake is the perfect guilt-free treat for any occasion!
This recipe is incredibly simple to prep with just a handful of basic ingredients. Made with whole grain oat flour, this sheet cake is naturally sweet as well as nutritionally beneficial. And the best part is oats contain a significant amount of fiber, protein, and healthy fats making this oat flour cake a great nutritious alternative to a more traditional sheet cake. Like other cakes, there are ways to keep it light and tender, reference this guide on fluffy cakes for more information.
Looking for more oat and oat flour recipes? Check out these oatmeal chocolate chip muffins, these oatmeal banana muffins and these oatmeal crepes.
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Gluten Free Oat Flour Cake at a Glance
This delicious oat flour cake recipe is one of my favorites because of its versatility. You can easily turn this traditional cake into a dozen cupcakes to switch things up. Also, try swapping out the cinnamon buttercream for this dairy free chocolate frosting or any other flavor you prefer. Here’s what else you’ll love about this sheet cake recipe:
- All you need is 8 simple ingredients.
- It’s made with healthy whole grain oat flour (need an alternative to oat flour?)
- The cake batter is easy to prep in 20 minutes.
- This vegan oat flour cake is gluten free, dairy free, egg free and xanthan gum free as written (with an option to be sugar free).
- It can be stored in the refrigerator to keep it fresh longer.
Ingredients & Substitutions
- Oat Flour - This recipe was tested using the oat flour from Nuts.com. Be sure to use oat flour that is labeled as certified gluten free, as talked about in this post on oats, not all oats are. You can make your own oat flour for this recipe if desired (follow the steps in the section below). I do not recommend substituting the oat flour with another gluten-free flour or a gluten free all purpose flour as the recipe has been developed specifically with oat flour. Although if you are looking for a substitute for other recipes, check out this post on oat substitutes.
- Granulated Sugar - For a refined sugar free version, you can swap out the white sugar for coconut sugar. Alternatively, for a sugar-free version, use this granular sweetener. This works great for a sugar free cake. Liquid sweeteners like maple syrup or honey are not recommended as they add more liquid to the recipe, altering the balance of dry ingredients to wet.
- Baking Powder - This is working with the yogurt to function as the thickening agent in the recipe. There is no alternative for the baking powder in this recipe.
- Salt - There is no substitution for the salt in this recipe.
- Dairy Free Plain Yogurt - A good substitute would be dairy free sour cream. You can also use regular sour cream or plain yogurt as an alternative if desired. Vegan buttermilk could also be used.
- Water - There is no substitute for the water in this recipe.
- Vegan Butter - In this cake, I use Earth Balance vegan butter. You can use coconut oil, olive oil, or regular butter as an alternative here if needed.
- Pure Vanilla Extract - There is no alternative for the vanilla extract in this recipe.
Exact measurements and directions, with step-by-step photos, for making this gluten free vegan cake are in the recipe card below.
How to Make Homemade Oat Flour
To grind your own oat flour at home, you need a food processor or flour grinder attachment, gluten-free oats, and a sifter.
Start by adding 1 cup of oats to the bowl of a food processor or in the grinder of the grain mill attachment. Process until a fine powder forms, which could take between 1-4 minutes.
If using a food processor, you may want to sift the flour to make sure no large pieces of oats remain. That is optional though.
The flour grinder will grind it into fine powder so you should not need to sift it.
Oat flour made at home will last about 2 months on the shelf at room temperature. Reference this flour storage chart for more information.
Step By Step Oat Flour Cake
You can mix up this easy 8 ingredient oat flour cake and have it ready to eat in less than an hour and a half. To get started, make sure all of your ingredients are at room temperature for the perfect batter cake consistency. First, combine the dry ingredients - oat flour, granulated sugar, baking powder, and salt - in the large bowl of a stand mixer (step 1 above). Set it aside. Then, in a small-medium bowl, stir together the dairy free yogurt, water, melted vegan butter, and vanilla extract (step 2).
Next, add the wet ingredients to the dry ones (step 3). Mix on low speed for 10 seconds to incorporate all of the ingredients. Stop the mixer and scrape down the sides of the bowl with a rubber spatula. Then, continue to mix on medium speed for 15 seconds to fully combine. Set the batter aside to rest for 30 minutes.
Meanwhile, preheat the oven to 350°F. Prepare a 9"x13" baking pan by lightly coating it with non-stick cooking spray. Once the batter is done resting, scrape it into the prepared pan with a rubber spatula and spread out the batter until even (step 4).
Baking & Frosting
Next, place the pan into the preheated oven and bake for 25-28 minutes or until a toothpick comes out clean. Allow the cake to cool completely in the pan on a wire cooling rack. Once the cake is completely cooled, frost the top of the cake with this cinnamon buttercream frosting, slice, and serve.
Storage Tips
This cake stores very well if stored in an airtight container at room temperature. It will last for up to two days if frosted.
The cake can be refrigerated for up to 5 days.
Freezing is not recommended as the cake does not taste as good when defrosted.
Add-ins & Cake Options
This sheet cake is delicious as-is but feel free to alter the cake to fit your needs:
Make 12 cupcakes: Portion the cake batter into 12 lined cupcake cups. Bake at 350F for 18-25 minutes. Start checking for doneness with a toothpick at 18 minutes.
Make a layer cake: This moist cake is a bit heavier than other gluten-free cake recipes, but it will still make a delicious layer cake.
Instead of a 9"x13" pan, line two 8" cake pans with parchment paper. Divide the batter evenly among the pans and bake at 350F for 20-28 minutes. Allow the cake to cool for 10 minutes in the pan, then remove from the pans to finish cooling on a wire rack.
When the cakes have cooled completely, place each layer in the refrigerator to chill. Frost the chilled cakes, then place the cake back into the refrigerator until serving.
Note: You may frost each cake separately for a single-layer cake or stack them for pretty cake layers.
Pro Tips
Although this 8 ingredient oat flour cake is quick and easy to put together, there are a few things to keep in mind when making this recipe. Follow these tips to ensure your cake comes out perfectly.
1. Use room temperature ingredients (except for the melted butter)
For this cake recipe, you need to use room temperature ingredients to ensure they are fully combined when mixed. The melted butter is the only exception here. This step is important because cold ingredients tend to not mix very evenly.
2. Measure ingredients by weight as specified
The oat flour and granulated sugar should be measured by weight in this recipe. Using a digital scale to measure ingredients by weight is the best way to get an accurate measurement. This is crucial for the texture of your cake. The baking masterclass explains why.
3. Don’t overmix the cake batter
Overmixing the batter can result in a cake with a dense and tough texture. Be sure to mix the ingredients just until they are combined to avoid overmixing.
4. Helpful tools
These tools will help make prepping your oat flour cake super quick and simple:
- Digital scale
- Mixer
- Small mixing bowl
- Rubber spatula
- 9”x13” baking pan
- Wire cooling rack
- Frosting knife
FAQs
This cake will stay fresh and moist for up to 2 days when stored at room temperature. Be sure to cover it well to keep it from drying out. For longer storage, you can keep it in the refrigerator. Freezing this cake is not recommended as it compromises the flavor.
Yes, homemade oat flour works great in this recipe. Be sure to use certified gluten free rolled oats. You can make oat flour on your own using a high-speed blender or food processor.
To turn this oat flour cake into cupcakes, swap out the 9”x13” pan for a standard cupcake/muffin pan. Bake the cupcakes at 350°F for 20-22 minutes. This recipe will make 12 cupcakes.
More Cake Recipes
More Oat Flour Recipes
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Recipe
8 Ingredient Oat Flour Cake (Gluten & Dairy Free)
Ingredients
- 250 grams oat flour about 2 cups
- 200 grams granulated sugar about 1 cup
- 1 Tablespoon baking powder
- ½ teaspoon salt
- 1 cup dairy free plain yogurt
- 6 Tablespoons water
- 4 Tablespoons vegan butter melted
- 1 Tablespoon vanilla extract
Instructions
- In the bowl of a stand mixer, combine oat flour, sugar, baking powder and salt.
- In a small bowl, stir together dairy free yogurt, water, melted vegan butter and vanilla extract.
- Add the wet ingredients to the dry and mix on low speed for 10 seconds to incorporate. Stop the machine and scrape the sides down.
- Mix on medium speed for 15 seconds to full combine.
- Set batter aside for 10 minutes.
- Meanwhile, preheat the oven to 350F. Spray a 9"x13" pan with cooking spray.
- Scrape batter into pan.
- Bake for 25-28 minutes or until a toothpick comes out clean.
- Cool completely in the pan on a wire rack.
- Frost with cinnamon buttercream frosting.
Notes
- This recipe was tested with this brand of oat flour. Alternatives to oat flour can be found here.
- A good substitute for the vegan yogurt would be vegan sour cream.
- Swerve sugar can be used in place of the granulated sugar.
- Regular butter or coconut oil can be used in place of the vegan butter.
- This cake will stay fresh for up to 2 days at room temperature. Refrigerate for longer storage. Freezing is not recommended as it compromises the flavor.
- The frosting recipe used on this cake is here. Use the cinnamon variation. This chocolate frosting would be excellent also.
Chris
Does it have to be vegan butter?Is that for the flavor? Could lard or coconut oil be used in its place?
Christine
Hi Chris,
Lard or coconut oil could be used, absolutely.
Christine
Michele
This was something I’ve been seeking for a long time. It is perfect and so moist and delicious. You can do so much with this perfect cake recipe. Thank you😊
Christine
Thanks Michele, so glad you enjoyed it! 🙂
Christine
Donna
Would this work as a layer cake? I want to actually make a butterfly cake for my sister's birthday this year. It sounds delicious!
Thanks!
Christine
Hi Donna,
So it probably would. It's a bit heavier in weight than other cakes, so my only thought would be the frosting in the middle - but here's what I'd recommend: Bake them in 8" pans then refrigerate the layers after they cool. When you're ready to frost, frost them cold, right from the refrigerator. Then just store it in the refrigerator. I think that would be your best bet.
Christine
Lori
I followed the recipe to a tee and it did not raise at all. 1/2" dense bars. Not what I expected.
Christine
Hi Lori, oh goodness, they should have risen a bit more than that.
Sounds like it might be a baking powder issue - sometimes if I have baking powder for a while, I test it before using it just to make sure it's still active. And then did you buy the oat flour or make it at home?
Christine