4-Ingredient Slow Cooker Baked Mostaccioli

This 4-Ingredient Slow Cooker Baked Mostaccioli is the ultimate comfort food for busy weeknights, potlucks, or family dinners. Tender mostaccioli pasta slowly cooks in rich marinara sauce before being layered with plenty of gooey mozzarella and savory Parmesan cheese. The slow cooker creates a perfectly cheesy baked pasta with almost no effort.

Serve this hearty pasta with a crisp green salad, warm garlic bread, or roasted vegetables for a complete meal. It’s also perfect for meal prep since leftovers reheat beautifully.

Why You’ll Love This Recipe

Only 4 simple ingredients.
No boiling the pasta first.
Perfect for potlucks and family gatherings.
Rich, cheesy, and incredibly comforting.
Easy slow cooker recipe with minimal cleanup.

Ingredients

1 pound uncooked mostaccioli pasta
48 ounces (about 6 cups) jarred marinara or spaghetti sauce
3 cups shredded mozzarella cheese, divided
1 cup grated Parmesan cheese, divided

Instructions

1. Lightly grease a 5 to 7-quart slow cooker with nonstick cooking spray or a thin coating of oil.
2. In a large bowl, combine the uncooked mostaccioli with the marinara sauce until every piece of pasta is evenly coated.

1. In a separate bowl, mix together 2 cups mozzarella cheese and ½ cup Parmesan cheese.
2. Spread one-third of the pasta mixture into the bottom of the slow cooker. Sprinkle with half of the cheese mixture.
3. Add another one-third of the pasta, followed by the remaining cheese mixture. Finish with the remaining pasta.

1. Combine the remaining 1 cup mozzarella and ½ cup Parmesan, then sprinkle evenly over the top.
2. Cover and cook on LOW for 2½ to 3½ hours, or until the pasta is tender and the cheese is melted and bubbly. Avoid opening the lid during the first 2 hours.

1. Check the pasta after about 2½ hours. Continue cooking if needed, checking every 20 to 30 minutes until perfectly tender.
2. For a golden-brown top, place the oven-safe slow cooker insert under the broiler for 3 to 5 minutes after cooking.
3. Let the casserole rest for 10 minutes before serving.

Variations & Tips

Add ½ to 1 cup ricotta cheese between the layers for a lasagna-style variation.
Use spicy arrabbiata sauce for extra heat.
Swap part of the Parmesan with Pecorino Romano for a sharper flavor.
If your slow cooker cooks hot, begin checking the pasta after 2 hours.
Store leftovers in the refrigerator for up to 4 days or freeze individual portions for up to 3 months.

Serving Suggestions

Pair this cheesy baked mostaccioli with garlic bread, a fresh Caesar salad, roasted broccoli, Brussels sprouts, or an antipasto platter. A glass of Chianti, Zinfandel, or sparkling water with lemon makes an excellent accompaniment.