Preheat oven to 325 F. Grease or spray a 9” x 5” pan. Set aside.
In a large bowl, add the softened cream cheese, melted butter, olive oil, whipping cream, vanilla and eggs. Blend with a handheld or stand mixer for 30 seconds. Scrape down and blend for 1 minute.
In a small bowl or plastic baggie, add the baking powder and xanthan gum. Mix together thoroughly.
Shake a portion over the liquid ingredients and blend. Continue shaking the baking powder/xanthan gum mix over the liquid and then blending with the mixer, until all the mix is gone and incorporated into the liquid ingredients.
In a flour sifter, add the protein powder, baking soda, salt and cream of tartar. Sift over the wet ingredients.
Stir by hand just until all the dry ingredients are mixed in.
Pour batter into the prepared pan and bake for 45 minutes or until golden brown.
Protein powder is an important ingredient in this recipe - nothing will directly substitute.
Make sure to sprinkle the gum and baking powder over the liquid ingredients first.
Mix the batter just until it's combined.
Enjoy this bread as-is or it makes a delicious sandwich.