Sautee red onion and I clove of smashed garlic in 1 T olive oil until softened & fragrant in small saucepan. Add lentils & water (2 cups) with 1/4 teaspoon salt uncovered, adding more water if necessary to keep lentils barely covered, until tender but not falling apart, 20 to 25 minutes. Remove from heat and season with salt.
While lentils simmer, heat remaining olive oil in a 12-inch heavy skillet over moderately high heat until hot but not smoking, then sauté shallots & remaining garlic with pepper and remaining 1/2 teaspoon salt, stirring, until golden brown.
Add thinly sliced fennel and saute until fennel is soft, stirring frequently, until fennel & shallot are golden brown, 5 to 10 minutes. Add 2/3 cup of chicken broth and simmer for a few minutes more.
While onion cooks, cut out and discard center ribs from kale and shop kale in think ribbons. Blanch kale in a 6-quart pot of boiling salted water uncovered, 5 minutes. Remove kale with a large sieve and drain.
Add the kale to the fennel & onion mixture and season with salt and pepper. Place kale, shallot, fennel mixture into a bowl and set aside.
Place the 2 links of sausage, out of their casings, in the same 12-inch heavy skillet over medium – high heat. Cook sausage, breaking up any lumps with a spoon, until browned, 5 to 7 minutes.
Cook pasta in boiling water, uncovered, until al dente. Reserve 1 cup pasta-cooking water, then drain pasta in a colander.
While the pasta is cooking add the fennel mixture and cooked lentils to the cooked crumbled sausage skillet. Loosen mixture with some additional chicken broth if necessary and simmer a few minutes to combine flavors.
Add pasta to the fennel, kale, lentil, sausage mixture along with about 1/4 cup of pasta-cooking liquid (or enough to keep pasta moist) and cook over high heat, tossing, 1 minute. Season with salt.
Serve immediately, with a dollop of goat cheese ricotta (optional)and shaved pecorino cheese
