Peel onion and garlic and chop finely. Clean the mushrooms and cut them in slices.
Heat the olive oil in a large pan. Briefly sauté the onion and garlic, then add the minced meat and fry. Remove the minced meat and onions from the pan.
Fry the mushrooms in butter, stir in the flour and bring to the boil with the vegetable stock and créme fraîche. Season with salt, pepper, lemon juice and sugar. Add the minced meat and reheat.
Meanwhile, heat the queen pies in the oven for 10 minutes. Then put on a plate, pour in the ragout, put on the lid and serve.