Preheat your oven to 425°F (220°C) and line a 12-cup muffin pan with paper liners.

In a large bowl, combine the pumpkin puree with both sugars. Whisk until the mixture is smooth and glossy. Add eggs, sunflower oil, and vanilla extract, whisking until well combined.

In a separate bowl, mix together flour, pumpkin pie spice, cinnamon, baking powder, baking soda, and salt. Slowly fold the dry mixture into the wet pumpkin mixture. Gently fold in milk until the batter is smooth.

In a small bowl, beat together the softened cream cheese, sugar, flour, and vanilla extract until creamy. Mix in the milk until smooth and set aside.

Divide the pumpkin batter evenly among the muffin cups, filling each to the rim. Using a piping bag, create a swirl with the cream cheese filling in the center and on top of the pumpkin batter.

Bake at 425°F (220°C) for 5 minutes, then lower the temperature to 350°F (175°C) and continue baking for 12-15 minutes, or until a toothpick inserted in the muffins comes out clean.

Let the muffins cool in the pan for 5 minutes before transferring to a wire rack.