Classic Coffee Cake

Ingredients

BATTER

• 1 1/4 c. (250 g.) granulated sugar 
• 3/4 c. (1 1/2 sticks) unsalted butter, room temperature
• 1/4 c. packed light brown sugar
• 3 large eggs
• 1 1/4 c. sour cream
• 1 tsp. pure vanilla extract
• 2 1/4 c. (270 g.) all-purpose flour
• 1/4 c. cornstarch
• 2 tsp. baking powder
• 1/2 tsp. baking soda
• 1 tsp. kosher salt

STREUSEL & ASSEMBLY

• 1 1/4 c. (250 g.) packed light brown sugar
• 1 c. (120 g.) all-purpose flour
• 3/4 c. (1 1/2 sticks) unsalted butter, melted
• 1 tbsp. ground cinnamon 
• 1/4 tsp. ground nutmeg
• Pinch of kosher salt

Directions

• BATTER
  1. Preheat oven to 350° and line a 13″ x 9″ pan with parchment. In a large bowl, using a handheld mixer on medium-high speed, beat granulated sugar, butter, and brown sugar until light and fluffy, 3 to 4 minutes. Add eggs, one at a time, beating to blend after each addition, then beat in sour cream and vanilla until just combined.
  2. In another large bowl, whisk flour, cornstarch, baking powder, baking soda, and salt until combined. Slowly add dry ingredients to egg mixture and beat on medium-low speed until just incorporated.
• STREUSEL & ASSEMBLY
  1. In a medium bowl, whisk brown sugar, flour, butter, cinnamon, nutmeg, and salt until combined.
  2. Add half of batter to prepared pan; spread in an even layer. Top with half of streusel, then add remaining batter and spread to edges of pan. Top with remaining streusel.
  3. Bake coffee cake until a tester inserted into the center comes out clean, 50 to 55 minutes. Transfer pan to a wire rack and let cool slightly.