1-Start by gathering your tools and ingredients to make the process smooth. This guide follows the recipe’s directions closely, with steps designed for easy following. Preheat your oven to 350ºF and prepare a 9×13 inch baking pan with nonstick spray or parchment paper for even baking.

2-First, make the crumb topping by combining 3 cups all-purpose flour, 2 cups packed brown sugar, 2 ½ tablespoons cinnamon, and 1 ½ teaspoons salt in a large bowl. Pour in 1 cup melted unsalted butter and mix until it’s sandy with some clumps, then set it aside. This step adds that irresistible topping everyone loves.

3-Next, peel, core, and dice the apples into ¼-inch chunks you’ll need 2.5 to 3 cups for the batter. In a small bowl, mix 3 cups all-purpose flour, 2 ½ teaspoons baking powder, and 1 teaspoon salt to prepare the dry ingredients.

4-In a large bowl, beat 1 cup softened unsalted butter and 2 cups granulated sugar until light and fluffy, which takes about 1-2 minutes. Add 4 large eggs and 2 teaspoons vanilla extract, beating well after each egg. Now, add half of the dry ingredients to the wet mixture and beat on low until combined.

5-Then, mix in 1 cup sour cream and ½ cup milk, beating for 30 seconds before adding the rest of the dry ingredients and the diced apples. Gently fold everything together to keep the batter light. Pour half the batter into your prepared pan and spread it evenly, then sprinkle 3 cups of the crumb topping over it.

6-Carefully add the remaining batter on top and sprinkle the rest of the crumb topping about 3.5 cups. Bake uncovered for 45 minutes, then cover with foil and bake another 35-45 minutes until a toothpick comes out clean. Let the cake cool before drizzling the glaze, made by whisking 1 cup powdered sugar, ½ teaspoon vanilla extract, and 2-4 tablespoons heavy cream or milk until smooth.