Coffee Cake

Directions

• Preheat the oven to 350°F and butter or spray a 9 x 13-inch pan.
• Make the streusel layer: In a small bowl, combine the flour, brown sugar, cinnamon, and salt. Use a fork to mash the butter into the mixture until completely combined and crumbly. Set aside. 
• Make the cinnamon layer: In another small bowl, combine the sugar, flour, and cinnamon. Set side, as well.
• Make the batter: In the bowl of your mixer, add the flour, sugar, baking powder, baking soda, and kosher salt. Using the paddle attachment for your stand mixer , stir on low to combine. Add the softened butter and beat on medium-low speed for 2 to 3 minutes, or until all of the butter is mixed in, and the mixture resembles moist sand. 
• Combine the wet ingredients and finish the batter: In a medium bowl, whisk together the sour cream, milk, eggs, and vanilla until combined. Add the mixture to the dry ingredients. Beat the batter on medium speed until you get a smooth batter. A few small lumps are totally fine. 
  
• Prepare the cake: Spread half of the batter into the prepared pan. Sprinkle the cinnamon-sugar layer over the top of the batter in an even layer. Spread the remaining batter over the top (this does require some patience since the batter likes to lift off the cinnamon-sugar layer). Top with the crumble mixture. 
• Bake the cake: Bake for 55 minutes or until a toothpick inserted in the center comes out clean. Cool on a rack for 1 hour (or until the cake comes to room temperature) before serving.
• Store the cake: You can make this cake a day or two in advance. Remove the cake from the pan and cover with plastic wrap. Keep it on the counter at room temperature.