Ingredients
For the topping:
- 3/4 cup gluten-free, all-purpose flour (make sure it has xanthan gum)
- 1/2 cup brown sugar packed
- 3/4 teaspoon cinnamon
- Pinch of salt
- 6 tablespoons cold unsalted butter cut into cubes
For the cake:
- 1 3/4 cups gluten-free, all-purpose flour
- 2 teaspoons baking powder
- 3/4 teaspoon baking soda
- 1/2 teaspoon salt
- 2/3 cup granulated sugar
- 2/3 cup sour cream
- 1/2 cup milk of choice (I used unsweetened almond milk)
- 1/3 cup unsalted butter, melted
- 2 large eggs at room temperature
For the filling
- 1/2 cup brown sugar packed
- 1/2 tablespoon cinnamon
Instructions
- Preheat your oven to 350 degrees Fahrenheit and line the bottom of an 9-inch cake pan with parchment paper, spraying the sides with cooking spray.
Making the topping:
- In a medium bowl, mix the flour, brown sugar, cinnamon, and salt. Use your fingers to rub in the butter until well mixed and large crumbles form. Refrigerate until ready to use.
Make the cake:
- In a medium bowl, whisk the flour, baking powder, baking soda, and salt.
- In a separate large bowl, whisk together the remaining cake ingredients.
- Whisk the dry ingredients into the wet ingredients until smooth and mixed.
Make the filling:
- Mix together the brown sugar and cinnamon in a small bowl.
Assemble:
- Pour half of the cake batter into the prepared pan. Sprinkle the filling evenly over top. Then, gently scoop the rest of the batter on top and smooth out evenly.
- Add the crumb topping and push in gently so it adheres to the batter.
- Bake until a toothpick inserted in the center comes out clean, about 1 hour to 1 hour and 10 minutes.
- Allow to cool in the pan completely before serving.