Crumb Cake

Ingredients

Crumbs

• 1 cup + 2 Tbsp (160g) all-purpose flour
• 1/3 cup (74g) packed light brown sugar
• 1/3 cup (72g) granulated sugar
• 1 tsp ground cinnamon
• 1/4 tsp salt
• 1/2 cup (4 oz) unsalted butter, melted

Cake

• 1 cup (143g) all-purpose flour
• 3/4 tsp baking powder
• 1/8 tsp baking soda
• 1/4 tsp salt
• 5 Tbsp (2.5 oz) unsalted butter, softened
• 1/2 cup (109g) granulated sugar
• 1 large egg
• 1 tsp vanilla extract
• 1/4 cup (2 oz) milk
• 1/4 cup (2 oz) sour cream

Instructions

• Preheat oven to 350 degrees. Butter an 8 by 8-inch baking dish then line with two sheets of parchment, butter parchment (alternately you can just butter and lightly flour the dish if you don't care to lift out the whole cake).

For the crumbs:

• In a mixing bowl whisk together brown sugar, granulated sugar, cinnamon and salt. Pour in melted butter (use a spatula to scrape out any excess) and stir to combine. Slowly add flour while mixing with a wooden spoon or spatula, and mix until no streaks of flour remain. Set aside to rest while cake batter is prepared.

For the cake:

• In a mixing bowl whisk together flour, baking powder, baking soda and salt for 20 seconds, set aside.
• In the bowl of an electric stand mixer fitted with the paddle attachment, whip together butter and granulated sugar until pale and fluffy. Mix in egg and vanilla. In liquid measuring cup used to measure milk, whisk together sour cream with milk. Add in 1/3 of the flour mixture to the butter mixture and blend just until combined, then add 1/2 of the milk mixture and mix just until combined. Repeat process once more, then end by mixing in last 1/3 of the flour mixture until nearly combined. Scape down sides and bottom of bowl using a rubber spatula and fold batter to fully incorporate.
• Pour batter into prepared baking dish and spread into an even layer. Break crumb mixture into pea size crumbs and drop evenly over batter. Bake in preheated oven until toothpick inserted into center comes out free of batter and cake doesn't sink when touched in center, about 32 - 35 minutes. Cool in cake pan 10 minutes, then using parchment overhang lift cake from pan and cool on a wire rack. Store in an airtight container.