Preheat oven to 350f. Grease 2 9" round pans, or 12 lined cupcake tins, with coconut oil.
In small sauce pan, boil 1 cup coffee. Chop pitted dates and add to boiling coffee. Remove from heat and allow dates to soak in the coffee for at least 10 minutes while preparing the remaining cake ingredients.
In medium bowl (or electric stand mixer bowl), add the Oat Flour, Protein Powder (or substitute ingredients), Cocoa, Baking Soda, Baking Powder, and Salt. Whisk thoroughly until well combined.
Add soured Milk (or buttermilk), Oil, and Vanilla extract. Mix for a few minutes until combined.
Add eggs one at a time, whisking thoroughly after each, until smooth batter forms.
Using an immersion blender or a smoothie blender, puree the coffee/date mixture until dates are smooth. Gradually pour this coffee and date mixture into the cake batter, mixing until silky smooth.
Pour cake batter into prepared and greased cake pans.
Bake cakes for 30-40 minutes (or 20-25 minutes for cupcakes) until done and inserted toothpick comes out clean.
Cool in cake pans for 5-10 minutes before removing from pans to finish cooling on cooling racks.