Add all ingredients to a mixing bowl.
Stir with a wooden spoon until roughly combined.
Continue beating the dough with the wooden spoon or with a mixer fitted with dough hook attachment (speed 2) for about 10-15 minutes. The dough should be well-combined, smooth, and you should see some bubbles forming. It will be very sticky so it’s not possible to knead it by hand (try to not add any more flour).
Leave to rest for 15 minutes.
While the dough is resting, bring a large pot of salted water to a boil.
Working in batches, press the dough through a ‘Spätzle press/maker’, a large-holed colander, or a slotted spoon with large holes. Push the batter with the back of a metal spoon directly into boiling water. Cook Spaetzle in batches so they won’t stay in the water for too long.
When the Spätzle come to the water surface they’re done - remove them from the water with a slotted spoon and transfer to a bowl with 2 tablespoons of butter.
While you’re adding Spaetzle to the bowl, stir them to coat them in butter - it will prevent them from sticking to each other.
Enjoy!