Peel and finely chop the onion. Fry in hot fat. Steam peas for 2-3 minutes
Wash the herbs and, except for a little chervil for garnishing, chop roughly. Finely dice the ham. Separate eggs. Mix egg yolk, quark, milk and semolina. Stir in cheese, except for something to sprinkle, and herbs. Season well with salt and pepper. Fold in onion, peas and ham, each except a little bit.
Beat the egg white until stiff, adding 1 pinch of salt and lemon juice. Fold into the quark mixture. Pour into a greased casserole dish sprinkled with breadcrumbs. Sprinkle with the rest of the onion, peas, ham and cheese
Bake the casserole in a preheated oven (electric cooker: 200 °C/circulating air: 175 °C/gas: level 3) for approx. 45 minutes. Cover towards the end if necessary. Garnish with the rest of the chervil. Serve with tomato sauce