- 3 cups all-purpose flour
- 1 cup brown sugar
- 1 cup white sugar
- 1 cup butter, softened
- 1/4 teaspoon salt
- 1 cup buttermilk
- 2 eggs, beaten
- 1 teaspoon baking soda
- 1 teaspoon ground cinnamon
- Preheat oven to 350 degrees F (175 degrees C). Grease a 9×13-inch baking dish.
- Mix flour, brown sugar, white sugar, butter, and salt together in a bowl until crumbly. Measure 1 cup mixture and set aside for later use.
- Stir buttermilk, eggs, and baking soda into crumbly mixture until batter is smooth. Pour batter into the prepared baking dish. Sprinkle reserved crumbly mixture over top of batter; top with cinnamon.
- Bake in the preheated oven until a toothpick inserted in the middle comes out clean, 45 to 50 minutes.