Gather Your Dry Goodies: In a medium bowl, simply whisk together the almond flour, brown sugar replacement, cocoa powder, chocolate protein powder, baking powder, optional espresso powder, and salt. Make sure it's all nicely combined.
Add the Wet Magic: Now, stir in the sour cream, egg, avocado oil, and vanilla extract until everything comes together smoothly. If your batter feels a bit too thick, gradually add a tablespoon or two of water until it's thick but easy to scoop.
Prep for Baking: Place 6 silicone muffin cups into an 8-inch round cake pan. Evenly divide your lovely batter among these cups.
Cover & Preheat: Gently cover the entire cake pan with aluminum foil (shiny side facing up!). Preheat your air fryer to 300°F (150°C) using the "bake" function if your model has it – this helps with even cooking.
First Bake Session: Carefully place the covered cake pan into your preheated air fryer. Bake for 15 minutes.
Uncover & Finish: After 15 minutes, remove the foil cover from the pan. Return it to the air fryer and continue baking for another 10 to 15 minutes, or until the cupcakes look beautifully risen and their tops are just firm to the touch.
Cool Down: Let these delightful cupcakes cool completely in the pan before handling. This step is crucial for perfect texture!
Time to Frost: Once fully cooled, generously top your cupcakes with your favorite keto frosting and get ready to enjoy a guilt-free treat!