Jumbo Apple-Walnut Muffins

Step 1
Preheat the oven to 375 degrees F (190 degrees C). Coat top and insides of jumbo muffin pan with cooking spray, or line with muffin papers.

Step 2
To make the muffins: Beat 1 ¼ cups sugar, 1/2 cup butter, vanilla, and salt together in a large bowl with an electric mixer until light and fluffy. Beat in eggs, one at time. Combine 1 ¾ cups of flour, baking powder, and 1/2 teaspoon cinnamon; stir into butter mixture, alternately with milk, until just combined. Fold in apples and walnuts. Scoop into muffin cups to fill 3/4 full.

Step 3
To make cinnamon crumble: Combine 1/4 cup white sugar, 3 tablespoons all-purpose flour, 2 tablespoons cubed butter, and 1/2 teaspoon of cinnamon in a medium bowl; mix together using a pastry blender or two butter knives until crumbly. Lightly sprinkle the tops of muffins with cinnamon crumble.

Step 4
Bake muffins in the preheated oven until tops are golden brown and a toothpick inserted into the center comes out clean, about 30 minutes. If they are browning too quickly, cover with foil. Remove from pans and cool on a wire rack.