In a microwave-safe mug, blend cottage cheese, egg, almond flour, erythritol, 1 tsp cinnamon, baking powder, and vanilla until smooth.
Microwave on high for 90 seconds to 2 minutes, until set in the center and a toothpick comes out clean.
While cake cooks, mix cream cheese, ½ tsp cinnamon, and powdered sugar until smooth.
Let cake cool for 1 minute, then spread icing on top and dig in warm.
