Bucatini Marinara with Sausage

Name: Bucatini Marinara with Sausage
Ingredients: 3 tablespoons butter; 1 medium onion, diced (about 1 1/2 cups); 1 medium carrot, diced; 4 cloves garlic, minced; 1 teaspoon dried oregano; 1/2 teaspoon dried crushed red pepper flakes; 2 (28-ounce) cans diced tomatoes; 1 dried bay leaf; 2 teaspoons sugar; Kosher salt; 1 pound bucatini pasta or thick spaghetti; 12 ounces ricotta cheese, room temperature; 1/2 cup julienne fresh basil leaves, for garnish; Grilled Sweet Italian Sausage, recipe follows; 8 links sweet Italian sausage