Line a mini muffin pan with plastic wrap or use a silicone mini muffin pan (my preference) and set aside.
In the bowl of a food processor, combine nut butter, oil, sweetener and extract. Process until smooth
Add in remaining ingredients (protein powder through sea salt). Pulse until combined and well incorporated. If the mixture looks too wet, add a bit more flour to reach a cake batter consistency (the bottom layer will firm up when refrigerated though).
Spoon into 12 individual mini muffin cups and refrigerate until firm (I left the cups overnight, but you also freeze the cups for an hour or so before finishing them with "frosting" layer if using).