Sour Cream Coffee Cake

Step 1
Preheat the oven to 350 degrees F (175 degrees C). Grease a 9×13-inch baking pan.

Step 2
To make the cake: Beat white sugar and 1 cup butter together in a large bowl with an electric mixer until light and fluffy. Add eggs one at a time, beating well after each addition; stir in sour cream and vanilla. Mix in 2 cups flour, baking powder, and salt. Spread 1/2 of the batter in the prepared pan.

Step 3
To make the filling: Mix brown sugar, 1/3 cup flour, 2 tablespoons melted butter, and cinnamon together in a medium bowl. Sprinkle 1/2 of the filling over cake batter in the pan. Spread remaining cake batter on top and sprinkle with remaining filling.

Step 4
Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 40 minutes.