This is a signature dish of Umbrian cooking. Both, lentils and sausages need to be of prime quality, The lentils should become soft and remain integer, not transform into mash as it happens with cheap lentils. In our region there are plenty of high quality lentils, even those famous ones from Ventotene island are grown by my friends from Casa Vespina. Every village butcher has its own sausage recipe. All are good and too salty. You can fail with sausages only buying them in a cheap suupermarket.
The lentils are boiled with a clove of garlic and some celery until al dente. I have a specific procedure to prepare sausages. I make holes into he sausage skin and boil them in some Grechetto until they release some fat. After this initial process I add other flavours, in this case a second clove of garlica and some finely chopped celery. Then fry for a while. Add a can of "polpa di pomodoro" and finish cooking the sausages. Add the lentils and cook together for other 5 minutes.
The typical "pane shapo"(unsalted bread) is appropriate with this dish.
I paired with two Rose' wines, and yes many pairings are possible. But: the elegance of th e TIXE (Pinot Grigio from Palazzone) is waisted with the salt and spices of the sausages. The Martavello, as derived from a red grape, went better. I can't imagine something better than a strong Sangiovese with sausages.