In a large skillet over medium heat, sauté one diced onion and three minced garlic cloves in a drizzle of olive oil for about 3–4 minutes until they become translucent. Add 1 pound of ground beef, breaking it apart, and cook until browned, approximately 5–7 minutes. Stir in 28 ounces of crushed tomatoes and 2 teaspoons Italian seasoning, then let the sauce simmer for 20–30 minutes until it thickens and flavors meld.

While the sauce simmers, mix together 15 ounces of ricotta cheese, 1 cup of shredded mozzarella, and ½ cup of grated Parmesan in a medium bowl. Add freshly chopped herbs and a pinch of salt and pepper to taste. Combine everything well until it's smooth and creamy.

In a large pot, boil water with a pinch of salt and carefully add the manicotti shells. Cook them for 7–9 minutes until they are al dente. Drain the shells gently in a colander and let them cool slightly.

Using a spoon or piping bag, carefully fill each manicotti shell with the cheese mixture, being mindful to avoid overfilling. Place the stuffed shells in a large baking dish, lined with a thin layer of the meat sauce.

Pour the remaining meat sauce over the stuffed manicotti in the baking dish. Sprinkle an extra 1 cup of mozzarella and a bit more Parmesan on top.

Preheat your oven to 375°F (190°C). Cover the baking dish with aluminum foil and bake for 40–45 minutes. Remove the foil for the last 10 minutes to allow the cheese to bubble and turn golden brown.