Wash parsley, shake dry and chop finely. Melt butter in a pot. Stir in flour. Deglaze with stock and milk. Simmer over low heat for about 5 minutes, stirring occasionally. Season to taste with salt, pepper and nutmeg. Stir in parsley, except for a little bit for sprinkling
Clean, wash, dab dry and cut into pieces. Dice the ham. Grate cheese. Heat oil in a large coated pan and fry gnocchi for about 2 minutes, turning them over. Add mangetouts and ham and fry for another 2-3 minutes.
Season with salt and pepper. Put everything into an ovenproof dish (approx. 17 x 25 cm). Pour sauce over it and sprinkle with cheese. Gratinate on the upper rail of the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: see manufacturer) for approx. 10 minutes. Sprinkle the casserole with the remaining parsley