Place softened cream cheese and salt in a bowl and mix together. Stir in butter and olive oil.
Then add heavy cream, eggs and egg whites using electric hand mixer until well blended.
Place all the dry ingredients (whey protein powder, cream of tartar, PH, XG, baking powder, salt) in a sifter and sift into the batter (stir as partial amounts of dry ingredients are sifted into the batter).
Pour batter into a loaf pan (lined with parchment paper or greased). Bake in preheated oven at 325 for 50 min.
Cool on cooling rack and serve!
You can store some slices in an airtight container for up to 3 days or freeze slices for up to 3 months.