1Combine brown sugar, white sugar, cinnamon, melted butter, and a pinch of kosher salt in a large bowl. Whisk until everything is saturated and the mixture resembles a thick, gooey consistency.
2Add all-purpose flour to the mixture. If the butter is not too hot, use your hands to incorporate the flour without overmixing, ensuring a nice crumbly topping.
3Cream together softened butter and sugar in a mixer until light and fluffy. If the mixer breaks, continue in a large bowl.
4Whisk eggs and vanilla extract together in a separate container.
5Add the egg and vanilla mixture to the creamed butter and sugar. Mix until incorporated.
6Add flour, baking powder, baking soda, and salt to the wet ingredients. Fold gently with a spatula to incorporate, bringing ingredients from the bottom to the top without overworking.
7Mix in sour cream or Greek yogurt, and milk without overworking the batter until smooth.
8Prepare baking pans by buttering them and lining them with crumpled parchment paper. Butter the parchment paper as well.
9Spread about half of the coffee cake batter into the prepared pans. The batter is thick and dense, but it will rise when baked.
10Sprinkle a good layer of the crumb topping over the batter. Gently press the crumb into the batter.
11Spread the remaining cake batter over the crumb layer, then top with more crumb. Press this final layer of crumb to ensure it sticks to the cake.
12Bake in a 350-degree Fahrenheit oven for 35 to 40 minutes, or until a toothpick inserted into the center comes out clean.
13Let the coffee cake cool to room temperature before glazing with an icing.
Ingredients
1 lb brown sugar
1 cup granulated sugar
1 lb butter, melted
2 tbsp ground cinnamon
1 pinch kosher salt
1.5 tsp vanilla extract
4.5 cups all-purpose flour
0.5 cup butter, softened
0.75 cup sugar
2 eggs
2 tsp vanilla extract
1.33 cup all-purpose flour
1 tsp baking powder
0.25 tsp baking soda
0.25 tsp salt
0.5 cup sour cream or Greek yogurt
2 tbsp milk
Equipment
large bowlwhiskmixerspatulabaking pansparchment papertoothpick
Tips
Crumple your parchment paper first to line your pans easier.
Press the crumb topping into the batter to ensure both layers stick together after baking.
Use your hands to evenly spread the batter in the pan.