Quarter the pumpkin, scrape out the seeds with a tablespoon. Clean about 1/3 of the seeds and put aside. Peel the pumpkin and cut into fine slices. Clean, wash and slice the parsnips.
Wash the thyme, shake dry and pluck the leaves from the stalks. Place the pumpkin, parsnips and thyme (except for 1 teaspoon for garnishing) on a greased pan of the oven lined with baking paper, sprinkle with sugar, salt and pepper.
Sprinkle with 2 tablespoons of olive oil. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for approx. 45 minutes. Meanwhile peel and chop the onions and garlic. Heat 2 tablespoons of olive oil in a saucepan and sauté the onions and garlic.
Take the vegetables out of the oven and add, except for 1-2 parsnip slices and pumpkin slices for garnishing. Deglaze with broth, bring to the boil. Puree with a blender and season again with salt and pepper.
Meanwhile, heat the oil in a large pan, fry the pumpkin seeds briefly while turning, remove. Press the sausage meat into the hot oil and fry for about 3 minutes, turning over.
Add meatballs and pumpkin seeds to the soup. Arrange in a tureen. Sprinkle with thyme and garnish with pumpkin and parsnip.