1-Preheat your oven: Preheat your oven to 350 degrees Fahrenheit and grease or line a baking pan with parchment paper to avoid sticking.

2-For the crumb topping: mix 1 cup packed light or dark brown sugar, 1/2 cup granulated sugar, 1 tablespoon ground cinnamon, and 1/2 teaspoon salt in a medium bowl.

3-Add 1 cup melted unsalted butter and gently mix in 2 and 1/2 cups all-purpose flour with a fork to keep it crumbly; set aside for later.

4-For the cake, whisk together 2 and 1/2 cups all-purpose flour, 1 teaspoon baking soda, 1/2 teaspoon baking powder, and 1/2 teaspoon salt in a separate bowl; set aside.

5-In another bowl, beat 3/4 cup softened unsalted butter and 1 cup granulated sugar until creamy and smooth.

6-Add 3 large eggs at room temperature, 1 cup full-fat sour cream at room temperature, and 2 teaspoons pure vanilla extract, mixing until combined (it’s okay if the batter looks a bit curdled at this stage).

7-Gradually mix in the dry ingredients on low speed until smooth, making sure not to over-mix to keep the texture just right.

8-Spread the batter evenly in the prepared pan, then firmly press the crumb topping on top to help it stick.

9-Bake for 45 to 55 minutes, or until a toothpick inserted in the center comes out clean. If the edges brown too quickly, cover loosely with foil to even things out.

10-Allow the cake to cool for 30 to 45 minutes before slicing, and dust with confectioners’ sugar if you want an extra touch.