My sister shared this 4 ingredient pasta secret with me. The ultimate rich and cheesy weeknight dinner

This slow cooker 4-ingredient spinach ricotta stuffed shells recipe is exactly the kind of weeknight magic my sister loves to share—rich, cheesy, and almost embarrassingly easy. Giant pasta shells are stuffed with a creamy ricotta and spinach mixture, nestled into a bed of marinara, then topped with melty mozzarella. The slow cooker does all the work while you handle homework, sports, or just put your feet up for a minute. It’s the kind of cozy, Midwestern family dinner that feels special without a lot of fuss, and it’s a great way to get some greens into everyone without a fight.

Serve these stuffed shells straight from the slow cooker with a simple green salad and garlic bread or warm breadsticks to soak up the extra sauce. A side of steamed broccoli or green beans works well if you want more veggies on the table. For adults, a glass of red wine or sparkling water with lemon pairs nicely with the rich, cheesy sauce. Put the slow cooker right in the center of the table (on a trivet), let everyone scoop their own shells, and pass extra Parmesan for sprinkling if you have it.

Servings: 6

24–26 jumbo pasta shells, uncooked

Spray the inside of your slow cooker with nonstick cooking spray or lightly grease it with a bit of oil to help prevent sticking.

Pour about 1 1/2 cups of the marinara sauce into the bottom of the slow cooker and spread it into an even layer so the shells have a saucy bed to sit in.

In a medium bowl, stir together the ricotta cheese and chopped spinach until the spinach is evenly distributed. If you like it extra cheesy, stir in 1/2 cup of the shredded mozzarella here as well.

Stuff each uncooked jumbo pasta shell with a heaping spoonful of the spinach-ricotta mixture. You want them generously filled, but not so full that the filling spills out completely.

As you stuff each shell, nestle it open-side up into the marinara in the slow cooker, creating a snug single layer. The shells can touch and be close together; that helps them stay upright and cook evenly.

Once all the shells are stuffed and arranged, spoon the remaining marinara sauce evenly over the tops, trying to cover most of the pasta so it can soften in the moisture while cooking.

Cover the slow cooker with the lid and cook on LOW for 3 to 4 hours, or until the shells are tender when pierced with a fork and the filling is hot. Avoid lifting the lid too often so the heat and moisture stay trapped inside.

About 20 to 30 minutes before serving, sprinkle the remaining shredded mozzarella cheese evenly over the shells. Cover again and let cook just until the cheese is melted and gooey.

Once the mozzarella is melted and the shells are fully cooked, turn off the slow cooker. Let the dish sit with the lid off for about 5 minutes to slightly thicken the sauce.

Use a large spoon or spatula to gently scoop out the stuffed shells, making sure to get plenty of the rich red sauce from the bottom of the slow cooker with each serving. Serve hot.

For picky eaters, you can chop the spinach extra fine so it practically disappears into the ricotta, or use just 1 cup of spinach instead of 2 for a milder flavor. If someone absolutely refuses spinach, leave it out and make plain cheese-stuffed shells, then serve a small salad or veggie tray on the side. To add a little protein without adding more ingredients, serve these shells with pre-cooked meatballs warmed in a separate pan of marinara, or crumble leftover cooked sausage or ground beef over the top when serving. For a lighter version, use part-skim ricotta and a lighter mozzarella; for an ultra-rich version, stir extra mozzarella into the filling and sprinkle some grated Parmesan on top if you have it on hand. You can also swap in a chunky vegetable marinara for more hidden veggies, or use a basil-heavy sauce for a brighter flavor. If your slow cooker runs hot, start checking the shells at the 3-hour mark so they don’t overcook and fall apart. Leftovers reheat nicely in the microwave with a spoonful of extra sauce to keep them moist.