Preheat the oven to 325°F (165°C). Grease all 12 cups of a muffin tin with butter or non-stick spray, if needed.
Make the crumb topping: In a small bowl, mix together brown sugar, cinnamon, and melted butter. Add flour and gently mix with a fork until crumbly (do not over mix). Set aside.
Prepare the muffin batter: In a large bowl, whisk pumpkin puree, maple syrup, melted butter, eggs and vanilla. Stir in flour, oats, pumpkin spice, and baking soda, mixing until just combined (a few lumps are fine).
Make the cream cheese filling: In a medium bowl, beat the cream cheese with a hand or stand mixer until smooth. Add vanilla and maple syrup, beating until creamy.
Assemble the muffins: Spoon 1 heaping tablespoon of muffin batter into each muffin cup. Add about 1 tablespoon of cream cheese filling. Top with another spoonful of batter, filling each cup to the top (some cream cheese may peek out). Sprinkle crumb topping over each muffin, gently pressing it into the batter.
Bake for 25–28 minutes, or until a toothpick inserted into a muffin comes out clean.
Cool: Place the muffin tin on a wire rack. Let muffins cool in the pan (they’ll be delicate when warm). Use a butter knife to loosen edges if needed.