I accidentally made this too good. Now it’s the only thing anyone wants me to bring to potluck.

This 4-ingredient slow cooker baked mostaccioli is the kind of happy accident every home cook secretly hopes for. I threw it together for a winter potluck—using pantry pasta, jarred sauce, and plenty of cheese—and it came out so comforting and gooey that now it’s the only dish I’m allowed to bring. Mostaccioli, a tubular pasta similar to penne but traditionally used in Italian-American baked casseroles, holds the sauce beautifully and stands up to slow, gentle cooking. The slow cooker mimics the low-and-slow oven-baked method, giving you tender pasta with a golden, stretchy cheese top and almost no effort.
Serve this slow cooker baked mostaccioli straight from the crock on a sturdy farmhouse-style table, with a big green salad dressed in a sharp vinaigrette to cut through the richness. Warm garlic bread or a crusty Italian loaf is perfect for swiping up the extra sauce and melted cheese. For a fuller spread, pair it with roasted vegetables—broccoli, Brussels sprouts, or carrots—or a simple antipasto plate with olives and marinated peppers. A light red wine, like Chianti or a fruity Zinfandel, or even sparkling water with lemon, balances the cozy, cheesy comfort of the dish.
4-Ingredient Slow Cooker Baked Mostaccioli
Servings: 8-10

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
Directions
Lightly grease a large oval slow cooker (5 to 7 quarts) with nonstick spray or a thin film of oil to help prevent sticking and make cleanup easier.
In a large bowl, combine the uncooked mostaccioli and the jarred marinara or spaghetti sauce. Stir well until every piece of pasta is thoroughly coated; this even coating helps the pasta cook uniformly in the slow cooker.
In a separate bowl, mix 2 cups of the shredded mozzarella with 1/2 cup of the grated Parmesan. This will be your cheesy middle layer that melts into the pasta as it cooks.
Spoon about one-third of the sauced mostaccioli into the bottom of the slow cooker and spread it into an even layer. Sprinkle half of the mozzarella-Parmesan mixture evenly over the pasta.
Add another one-third of the sauced mostaccioli over the cheese layer, then sprinkle the remaining mozzarella-Parmesan mixture evenly over that. Finish with the last one-third of the sauced mostaccioli, smoothing the top slightly with the back of a spoon.
In a small bowl, combine the remaining 1 cup shredded mozzarella and remaining 1/2 cup grated Parmesan. Sprinkle this mixture evenly over the top of the pasta to create a generous cheese blanket that will turn golden and bubbly.
Cover the slow cooker with its lid and cook on LOW for 2 1/2 to 3 1/2 hours, until the pasta is tender but not mushy. Try not to open the lid during the first 2 hours, as you’ll lose heat and slow down the cooking.