Beat cream cheese, egg yolk, sugar, and vanilla until smooth. Chill in the freezer while preparing the batter.
For the topping, stir brown sugar, cinnamon, and melted butter together, then mix in flour with a fork until crumbly. Refrigerate.
Whisk flour, baking powder, baking soda, salt, cinnamon, and pumpkin pie spice in a large bowl.
Whisk brown sugar, granulated sugar, eggs, pumpkin puree, oil, milk, and vanilla in a separate bowl until smooth.
Pour wet ingredients into dry ingredients. Fold just until flour disappears. Rest batter 15 minutes.
Preheat oven to 425°F (220°C). Line muffin pan with paper liners.
Spoon 1 tablespoon of batter into each liner. Add 1 tablespoon of chilled cream cheese filling to the center. Cover with more batter, filling liners near the top.
Sprinkle crumb topping over each muffin, if using.
Bake at 425°F for 5 minutes. Lower oven to 350°F (175°C) without opening the door. Bake 15 to 17 minutes, until a toothpick inserted into the side comes out with a few moist crumbs.
Cool in the pan for 10 minutes, then transfer to a wire rack.
Notes
Chill the cream cheese filling until firm before filling the muffins — this keeps it centered instead of sinking or spreading into the batter.Approximate Nutrition (per muffin): Calories: 245 | Carbohydrates: 29g | Protein: 4g | Fat: 13g | Fiber: 1g | Sugar: 17g | Sodium: 220mgNutrition information is automatically calculated and should be used as an approximation only.