Preheat oven to 375°F (190°C). Line a muffin tin with paper liners and lightly spray with nonstick spray.
In a large bowl, beat melted butter and brown sugar until smooth. Add eggs, vanilla, pumpkin purée, and Greek yogurt. Mix until fully combined.
½ cup unsalted butter, 1½ cups pumpkin purée, ¾ cup light brown sugar, 2 large eggs, ¼ cup Greek yogurt, 1 teaspoon vanilla extract
In another bowl, whisk together flour, baking soda, salt, pumpkin spice, and cinnamon. Gently fold the dry ingredients into the wet mixture just until combined—don’t overmix. Let the batter sit while you prepare the topping.
1¾ cups all-purpose flour, 1 teaspoon baking soda, 1 teaspoon pumpkin spice, ¼ teaspoon salt, ½ teaspoon ground cinnamon
In a small bowl, mix flour, brown sugar, and cinnamon. Stir in melted butter until the mixture becomes crumbly.
¾ cup all-purpose flour, ⅓ cup light brown sugar, 1 teaspoon ground cinnamon, 3 tablespoons unsalted butter
Spoon the batter into muffin cups, filling about ¾ full. Sprinkle each with a generous amount of streusel topping. Bake for 18–20 minutes, or until a toothpick inserted in the center comes out clean. Cool in the pan for 5 minutes, then transfer to a wire rack to cool completely.
Beat the softened cream cheese until smooth. Add confectioners’ sugar, vanilla, and 1 tablespoon milk. Beat until creamy, adding more milk if needed for a spreadable texture.
4 ounces cream cheese, ½ cup confectioners’ sugar, ½ teaspoon vanilla extract, 1-3 tablespoons milk
Once muffins are fully cooled, pipe or spread the cream cheese frosting on top. Serve and enjoy!