Baked Crumb Cake Doughnuts

For the doughnuts:
Preheat oven to 350ºF. Spray donut pan with nonstick spray.

In a bowl, whisk together flours, baking powder, salt, cinnamon and nutmeg.

In a large bowl, whisk together butter and sugar until combined. Add dry ingredients and eggs, mixing until batter is just combined. Whisk in vanilla extract, then stir in buttermilk until batter is smooth.

Use a spoon and add the batter to the donut pan until each mold is about 3/4 full. Bake for 13–15 minutes, until set and slightly golden. Remove and let cool. Once cool, dip in glaze and sprinkle crumb topping. Serve immediately.

For the espresso glaze:
Whisk together powdered sugar, espresso and vanilla extract in a large bowl until smooth and glaze-like. If mixture is too thick, add more espresso 1 tablespoon at a time and whisk well.

For the crumb topping:
Whisk together sugars, cinnamon, salt and melted butter until combined. Whisk for a good minute or two until sugar begins to dissolve, then use a wooden spoon to stir in flour. The mixture will be crumb-like and dry, almost like a sludge or paste. This is what you want! 

Heat a large skillet over medium heat and add a few handfuls of the crumbs. Stir and toss with a wooden spoon until they are golden and crumbly (you can always crumble more after), about 5–6 minutes. Let cool on a piece of parchment paper. Sprinkle on glazed doughnuts.