1Combine the eggs, flour, water and a pinch of salt. Add more flour if needed, until the mixture resembles a thick pancake batter.
2Prepare a pot of boiling water and season with salt. Bring the water to a boil, dip a spoon in it, then scrap bits of dough in the boiling water.
3Simmer until the dumplings float to the top.
4In the meantime, heat the butter and oil in a pan on medium heat. Add the onion, sauté for 4 minutes, add the garlic, cook for 2 more minutes.
5Add the snap peas, a big pinch of salt, lemon zest and cook for 2 to 3 minutes, until they’ve softened, but still look bright green and crunchy.
6Add the Parmesan and mozzarella cheese to the pan, then toss the cooked späetzle with a splash of pasta water. Simmer everything for 3 to 4 minutes, until the cheese has melted and the sauce looks emulsified.