Best Stuffed Rigatoni Recipe with Sausage | Tasting Table

Name: Best Stuffed Rigatoni Recipe with Sausage | Tasting Table
Ingredients: ½ pound dried rigatoni (medium to small works the best); ¾ pound Italian sausage, uncased; 1 large egg; Olive oil; 1 cup minced onion; 2 tablespoons thinly sliced garlic (from about 3 cloves); 20 cherry tomatoes, halved (approximately 2 cups); 2 tablespoons butter; Reserved pasta water; 1 cup rapini, chopped fine; 1 teaspoon chopped anchovy fillets; Parmesan or pecorino cheese, to garnish; Juice from 1 lemon; Salt and pepper, to taste