Cut a generous lid off the pumpkin. Remove the core with the pulp up to about 2 cm edge from the pumpkin. Peel the "lid" of the pumpkin and roughly dice the flesh from the lid and the rest of the fruit. Peel potatoes and also dice them roughly. Clean, wash and cut the zucchini into pieces.
Peel and chop onion and garlic. Heat oil in a pan. Fry the minced meat until crispy brown. Season with salt and pepper. Put the minced meat in a large pot. Add the onion, garlic and diced potatoes and fry briefly. Pour on the stock and cook in a closed pot for about 10 minutes. Add pumpkin and zucchini and braise for another 10 minutes. Finally pour on condensed milk, bring to the boil and stir in the sauce thickener.
Add the onion, garlic and diced potatoes and fry briefly. Pour on the stock and cook in a closed pot for about 10 minutes. Add pumpkin and zucchini and braise for another 10 minutes. Finally pour on condensed milk, bring to the boil and stir in the sauce thickener. Season everything with salt, pepper and marjoram. Pour the ragout into the hollowed pumpkin and serve immediately