For the pancakes, mix flour, milk, eggs and salt with the whisk of the hand mixer. Heat the fat in a frying pan, fry 4 pancakes one after the other until golden brown and keep warm.
For the filling, clean, wash and slice the mushrooms. Clean and wash spring onions and cut them into rings. Fry the minced meat in hot oil. Add mushrooms and spring onions and steam. Chop the tomatoes in the tin.
Drain the corn. Add both to the mince and cook for about 15 minutes. Season to taste with salt, pepper and paprika. For the sauce, peel onion, dice finely and fry in hot fat until translucent. Add flour and sauté.
Add the stock and milk bit by bit, stirring constantly, and simmer for about 15 minutes at low heat. Grate cheese and stir 2/3 into the sauce. Season with salt and pepper. Fill the pancakes with the minced meat mixture and fold them up like bags.
Place in a flat ovenproof dish. Pour the sauce over it, sprinkle with the remaining cheese and bake in a preheated oven (electric: 200 °C/ gas: level 3) for approx. 15 minutes. Wash parsley, dab dry, chop and sprinkle over the pancakes.