Instructions
Follow the steps and taste along the way.
Prepare the lentils and vegetables
Rinse the lentils in cold water. Dice the onion, carrot, and celery finely, and cut the leek into thin half-moons. Heat the oil in a pot and cook the onion over medium heat for 3 minutes, until softened and lightly golden at the edges. Add the carrot, celery, and leek and cook for another 4 minutes.
Cook the lentils
Add the rinsed lentils, stock, bay leaf, 5 g of salt, and black pepper to the pot. Bring to a gentle simmer, cover, and cook over low heat for 30 to 35 minutes. Stir occasionally; the lentils should be tender but not falling apart. Remove the bay leaf.
Make the Spätzle dough
While the lentils cook, combine the flour for the Spätzle, eggs, 120 ml of water, and 3 g of salt. Beat the dough vigorously with a wooden spoon for 3 to 4 minutes, until smooth, thick, and elastic, with bubbles beginning to form. Let it rest for 10 minutes.
Thicken and season the lentils
Melt the butter in a small saucepan, add the flour for thickening, and stir for 1 to 2 minutes to make a pale roux without browning it. Stir about 100 ml of hot liquid from the lentils into the roux, then pour the mixture back into the pot and simmer for 3 minutes. Remove from the heat, stir in the vinegar and mustard, and taste: the result should be pleasantly tangy, not sharply vinegary.
Cook the homemade Spätzle
Bring 3 l of water and 15 g of salt to a boil in a large pot. In batches, press the dough through a Spätzle press or scrape it from a board into the water with a spatula. Once the Spätzle float to the surface, cook them for 1 more minute, then remove them with a slotted spoon. The finished Spätzle should be soft and springy, not overcooked.
Heat the sausages and serve
Heat 700 ml of water in a small pot until just below boiling, then lower the heat and add the sausages. Heat them for 6 to 8 minutes without letting the water boil vigorously, so they do not split. Taste the lentils once more; if they are too thick, stir in 30 ml of hot water. Serve the hot lentils with the Spätzle and sausages.
