Braciola and Sausage Sunday Gravy

Name: Braciola and Sausage Sunday Gravy
Ingredients: 6 very thin top round steaks, about 8 ounces; Salt and freshly ground black pepper; 1 cup grated pecorino cheese, plus more to pass at the table; 1/2 cup homemade stale white breadcrumbs or panko, toasted; 3/4 cup fresh flat-leaf parsley leaves, chopped; 1/4 cup pine nuts or sliced almonds, toasted; 2 teaspoons lemon zest; 4 ounces salami or prosciutto di Parma, finely chopped; 6 cloves garlic, 3 minced or grated, 3 crushed; 2 small chile peppers such as Italian cherry or Fresno, 1 seeded and finely chopped (can substitute 1 teaspoon dried red crushed pepper flakes), and 1 thinly sliced; 5 tablespoons EVOO; 6 links hot Italian sausage; 1 teaspoon fennel seeds, 1/3 palmful; 1 cup dry red wine; 2 large cans Italian San Marzano tomatoes; 1 bay leaf; 1 small carrot, peeled and halved; 1 small rib celery, halved; 1 small onion, halved and peeled; 2 cups passata or tomato puree; A handful of fresh basil leaves, torn; 1 large red or yellow onion, thinly sliced; 2 cubanelle peppers, thinly sliced; 1 large red bell pepper, thinly sliced; 1 cup chicken or beef stock; 1 tablespoon tomato paste; 2 to 3 tablespoons butter; 1 1/2 pounds spaghetti