ricotta cheese (about 800 grams) • cooked spinach, sautéed with 1 garlic clove (about 350 grams) • large egg • grated Parmesan cheese • Salt and pepper, to taste • canned crushed or whole peeled tomatoes (about 800 grams) • onion • garlic clove • Extra-virgin olive oil, fresh basil, and salt, to taste • milk (about 800 ml) • unsalted butter (about 80 grams) • all-purpose flour (about 60 grams) •