Preheat your oven to 350°F. This ensures that your cake bakes evenly from the moment it goes in.
Prepare a 9×9-inch glass baking dish by spraying it with non-stick cooking spray. This will help you easily remove the cake once it's baked.
In a medium mixing bowl, whisk together 2 cups of all-purpose flour, 1 tablespoon of pumpkin pie spice, 1 teaspoon of cinnamon, 1 teaspoon of baking soda, ½ teaspoon of salt, and 2 teaspoons of baking powder. The goal is to combine the dry ingredients thoroughly so they mix well with the wet ingredients later on.
In a separate bowl, mix together 2 large eggs, ⅓ cup of vegetable oil, ¾ cup of packed light brown sugar, 1 cup of pure pumpkin puree, 1 teaspoon of vanilla extract, and ½ cup of whole milk. Beat the mixture until it's smooth and well combined. You want a creamy consistency for the wet batter.
Gently fold the wet ingredients into the dry ingredients. Make sure to stir just until combined; over-mixing can lead to a dense cake.
Spread the batter evenly into the prepared baking dish. Use a spatula to ensure it's smooth across the top.
In another medium bowl, whisk together ½ cup of all-purpose flour, 1 teaspoon of baking powder, ¼ cup of packed light brown sugar, and 1 teaspoon of ground cinnamon for the streusel topping. This blend will add that delightful crunch.
Cut ¼ cup of cold salted butter into small pieces and use a pastry blender or fork to mix it into the flour mixture until it resembles small peas. This creates that crumbly texture in your streusel.
Stir in 1 tablespoon of milk or cream until the mixture clumps together slightly. Sprinkle this streusel over the cake batter in the baking dish.
Bake the Pumpkin Coffee Cake for 40 to 45 minutes. It’s done when a toothpick inserted into the center comes out with just a few moist crumbs. Keep an eye on it!
Allow the cake to cool in the pan before adding the glaze. This cooling period helps the texture become perfect.
In a small bowl, whisk together the glaze ingredients: ½ cup of powdered sugar and enough 1 to 2 tablespoons of milk to reach a thick drizzle consistency. Drizzle it over the cooled cake.
Cut into pieces and serve. Enjoy the delightful flavors and the joy it brings to your table.