For the spaetzle, wash the herbs, shake dry, pluck the leaves and chop them. Puree eggs and herbs with a hand blender. Sieve 300 g flour into a bowl, mix with 1 teaspoon salt and a little nutmeg.
Stir in the egg mixture and beat with a wooden spoon (with hole) until the dough starts to bubble. The dough should flow slowly from the spoon without tearing. If it is too firm, fold in 2-3 tablespoons of cold water.
Cover and let rest for about 30 minutes.
Meanwhile clean the mushrooms, wash them briefly if necessary and cut them in half or quarters depending on size. Peel and finely dice the onions. Dab meat dry. Heat 2 tablespoons of oil in a large pan. Fry the medallions for 2-3 minutes while turning them, remove them and place them in an ovenproof dish.
Season with salt and pepper.
Preheat oven (electric cooker: 200 °C/circulating air: 175 °C/gas: see manufacturer). Heat 1 tbsp. oil in the frying fat, fry the mushrooms in it for approx. 5 minutes. Fry the onions briefly. Dust with 2 tbsp. flour and sauté briefly.
Add 1⁄4 l water and cream, stir in broth, bring to the boil and simmer for about 1 minute. Season sauce with salt and pepper.
Spread the sauce over the meat. Gratinate in a hot oven for about 15 minutes. In the meantime, press the spaetzle dough in portions through a spaetzle press in plenty of boiling salted water and simmer for 1-2 minutes until they rise to the surface.
Lift out with a skimmer, place in a sieve, quench cold and drain. Heat the butter in a pan and toss the spaetzle in it. Season with salt and pepper if necessary. Arrange meat with sauce and spaetzle.