Preheat the oven to 375°F (f oven). Line a standard muffin pan with paper liners or lightly coat with nonstick cooking spray.

In a small bowl, combine the flour, brown sugar, and cinnamon. Cut in the cold butter using a pastry blender, fork, or your fingertips until the mixture looks like coarse crumbs. This buttery crumb mixture will bake into a nutty streusel with a little crunch. Set aside.

In a medium bowl, whisk flour, baking soda, salt, cinnamon, ginger, nutmeg, cloves, and cardamom together until fully blended.

In a large mixing bowl, use a hand mixer or stand mixer fitted with the paddle attachment to cream the room temperature butter and white sugar until light and fluffy. Add vanilla extract and large eggs, mixing until smooth. Stir in the pumpkin purée until the mixture is thoroughly combined.

Gradually add the dry ingredients to the wet ingredients, mixing just until combined. Use a rubber spatula to scrape the sides and bottom of the bowl. Avoid overmixing — this helps the muffins bake up soft with a tender muffin crumb.

Scoop the muffin batter into the prepared muffin tin, filling each muffin cup about ¾ full. Sprinkle a generous amount of the streusel topping over the top of the batter in each cup.

Bake the muffins for 20–25 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs (not wet batter). Cool the muffins in the pan for 5 minutes, then transfer to a wire rack to cool completely.

For an extra touch of sweetness, mix the powdered sugar, maple syrup, heavy cream, cinnamon, cardamom and vanilla extract in a small bowl until smooth. Drizzle over cooled muffins.