Coffee cake crumb donuts that are baked and not fried! Soft, fluffy vanilla cake donuts with a delicious cinnamon brown sugar crumb topping and baked in a doughnut pan. It's such a delicious donut, and it's ready in just 30 minutes!
For the crumb topping, combine butter, sugar, and cinnamon. Add the flour. Using a fork, mix until the mixture is crumbly. Set aside.
In a large bowl, whisk the flour, sugar, baking powder, salt, cinnamon, and nutmeg. Set aside.
In a medium bowl, whisk together the egg, sour cream, melted butter, and vanilla. Fold the wet ingredients into the dry ingredients.
Use a spoon or a piping bag to fill donut cavities with batter ¾ full. Top each donut with just enough crumb topping to fully cover the batter.
Bake for approximately 15-18 minutes or until a toothpick comes out clean. Allow to cool slightly before flipping the pans upside down over a wire rack.
In a small bowl, whisk together powdered sugar, milk, and vanilla. Add to a piping bag and drizzle over the cooled donuts.