Instructions

1. Preheat the oven to 180°C/350°F (160°C/320°F for a ventilated oven).
   
2. Meanwhile, cut the butter into cubes and let it soften at room temperature for 10 minutes.
   
3. Cut the pumpkin into cubes, place it on parchment paper, and bake in the preheated oven for 20 minutes (15-18 minutes in a ventilated oven).
   
4. Once the butter has softened, place it in a deep bowl, add the sugar, and mix with a mixer (using a whisk attachment) until smooth. Add the eggs and mix again.
   
5. By now, the pumpkin should be ready. Put it in a blender and blend until smooth.
   
6. Transfer the pumpkin puree to a large bowl. Add the butter mixture, sifted flour, and baking powder. Mix well with a mixer.
   
7. Place half of the batter into muffin tins, filling them 1/3 full. Add a teaspoon of pumpkin jam in the center of each, then cover with the remaining batter.
   
8. Bake in the preheated oven for 20 minutes (15-18 minutes in a ventilated oven).