Preheat oven to 350F and line a muffin tin with parchment or silicone liners.
Combine sour cream, eggs, espresso powder, and vanilla extract in a large blender jar. Blend about 30 seconds.
Add the almond flour, sweetener, coconut flour, baking powder, cinnamon, and salt. Blend again until smooth, about 30 seconds to a minute. If your batter is overly thick, add 1/4 to 1/2 cup of water to thin it out (different brands of almond flour can vary).
Divide the mixture among the prepared muffin cups and bake 23 to 25 minutes, until just golden brown and firm to the touch. Remove and let cool completely.
In a small bowl, whisk together the powdered sweetener and cream. Drizzle over the cooled muffins. Sprinkle with a little cinnamon.