1.
Combine brown sugar, flour, and cinnamon. Cut in butter until crumbly. Refrigerate.
| 2⁄3 cup |
Brown Sugar |
| 3⁄4 cup |
All-Purpose Flour |
| 2 1⁄2 tsp |
Cinnamon |
| 6 tbsp |
Unsalted Butter |
2.
Preheat oven to 350 °F. Grease or line an 8-inch square pan with parchment paper.
3.
Whisk together flour, baking powder, baking soda, and salt. Set aside.
| 1 1⁄3 cup |
All-Purpose Flour |
| 1 tsp |
Baking Powder |
| 1⁄4 tsp |
Baking Soda |
| 1⁄4 tsp |
Table Salt |
4.
Cream butter and sugar until light and fluffy. Add eggs and vanilla, mixing well. Stir in sour cream.
| 1⁄2 cup |
Unsalted Butter |
| 3⁄4 cup |
Granulated Sugar |
| 2 each |
Eggs |
| 2 tsp |
Vanilla Extract |
| 1⁄2 cup |
Sour Cream |
5.
Add dry ingredients to wet, mixing just until combined. Stir in milk.
6.
Spread half the batter in the pan. Sprinkle half the crumb mixture. Top with remaining batter, then the rest of the crumb mixture.
7.
Bake for 32–38 minutes or until a toothpick comes out clean. Cool in pan for 15 minutes.
8.
Whisk together icing ingredients and drizzle over warm cake. Slice and serve.
| 1 cup |
Powdered Sugar |
| 1⁄2 tsp |
Vanilla Extract |
| 2 tbsp |
Heavy Cream |