Sausage, pasta, spinach, and cheese. Baked until bubbly and golden. This is the ultimate comfort food that’s surprisingly easy to throw together, and it’ll make you look like a total kitchen rockstar.
The magic is in the layering. A simple, savory meat sauce with wilted spinach gets tangled up with al dente pasta, then meets a creamy ricotta-mozzarella mixture. Everything bakes together into this gorgeous, bubbly, scooped-from-the-pan masterpiece.
I started making this when I needed a guaranteed crowd-pleaser that didn’t require a ton of fussy steps. Now it’s our go-to for a hearty, satisfying dinner that tastes way more impressive than the effort involved. That cheese pull alone is worth it!
Why Undercook the Pasta Before Baking
Pasta keeps cooking AFTER it hits the oven. The sauce, the cheese, the covered dish…. it all creates steam and residual heat that finishes the job. Boil to full package time and you’re signing up for MUSH. Nobody wants that.
Two minutes under al dente is your sweet spot. The noodles should still have a slight bite when you drain them, and they’ll finish perfectly in those 15-20 minutes of baking, soaking up sauce without turning into paste. Overcooked pasta also BREAKS apart during layering, leaving you with a fragmented mess instead of clean, scoopable layers.
Taste a piece before draining. Firm but not crunchy, with a tiny white dot at the very center. THAT’S your cue to pull. (Err on the firmer side…. oven time fixes everything.)
How to Layer Baked Mostaccioli
- SPREAD 1/2 cup meat sauce on the bottom of a greased 9×13 inch dish. (Prevents sticking, obviously.)
- LAYER half the cooked mostaccioli over the sauce.
- Add HALF the cheese mixture and spread it evenly.
- SPOON on half the remaining sauce (about 1.5 cups).
- REPEAT with the rest of the pasta and cheese mixture.
- TOP with the final sauce layer and ALL remaining mozzarella and Parmesan. (Cover every inch!)
Stack with purpose, bake until bubbly, and devour without restraint.
Fresh vs. Pre-Shredded Mozzarella
Pre-shredded mozzarella contains anti-caking agents like cellulose that create a grainy, clumpy melt… not what you want here! Buy a BLOCK of low-moisture whole milk mozzarella and shred it yourself on the large holes of a box grater.
Skip fresh balls packed in water (way too much moisture, will make your mostaccioli soupy). Freshly shredded gives you a smooth, creamy top every single time.
Make-Ahead & Freezing Tips
- ASSEMBLE 24 HOURS AHEAD: Build the dish, cover tightly, refrigerate. Add 10-15 minutes to the bake time when going in cold.
- FREEZE UNBAKED: Plastic wrap, then foil, up to 3 months. Thaw overnight, or bake frozen at 375°F for 60-75 minutes. Foil on for the first 45 to protect the cheese.
- PORTION LEFTOVERS: Airtight containers, then reheat at 350°F covered for 20 minutes. Microwave single servings with a splash of water.
- SAUCE-ONLY SHORTCUT: Meat sauce freezes well for 3 months. Stir in fresh spinach when reheating (thawed spinach turns limp and gray, just saying).
- UNDERCOOK THE PASTA: Boil 2 minutes shy of al dente if freezing. Noodles soften during the second bake… plan accordingly!
Storage & Reheating Instructions
Refrigerate leftovers in an airtight container for up to FOUR days. The pasta soaks up sauce as it sits, so add a splash of marinara before reheating!
Cover with foil and bake at 350°F for 20 minutes (oven is BEST for keeping that cheese layer intact). Single portions? Microwave on medium in 60-second bursts, stirring between rounds.
Freeze up to THREE months wrapped tight in plastic and foil. Thaw overnight in the fridge first.
More From the Kitchen
- Baked Ziti with Ground Turkey and Spinach
- Crockpot Ground Beef Pasta
- Baked Mostaccioli with Cottage Cheese
- Comforting Ground Beef Pasta Bake
- Comforting Baked Ziti with Ground Turkey and Cottage Cheese
- Easy Baked Ziti with Ground Turkey
Estimated Nutrition
Estimated nutrition for the whole recipe (without optional ingredients):
- Calories: 3400-3700
- Protein: 160-185 g
- Fat: 185-210 g
- Carbohydrates: 225-250 g
Ingredients
For the meat and sauce:
- 1 lb italian sausage (I use Johnsonville mild links with casings removed)
- 1 large onion (diced into 1/2-inch pieces)
- 5 cloves garlic (minced)
- 1 tsp salt
- 1.5 tsp italian seasoning
- 3.5 cups marinara (I prefer Rao’s Homemade for a rich, authentic flavor)
- 2.5 cups spinach (roughly chopped)
- 1/4 tsp red pepper flakes
For the pasta and cheese mixture:
- 14.5 oz mostaccioli pasta (boiled 2 minutes less than package directions for al dente)
- 3.5 cups mozzarella (freshly shredded for better melting)
- 2 cups ricotta
- 1/2 cup parmesan (I like Sargento shredded parmesan for this)
- 1 large egg
- Pinch of nutmeg
Step 1: Chop Aromatics and Preheat Oven
- 1 large onion
- 5 cloves garlic
- 2.5 cups spinach
Dice the onion into 1/2-inch pieces, mince the garlic, and roughly chop the spinach.
While you’re prepping, preheat your oven to 425°F and grease a 9×13 inch baking dish.
This prep work ensures everything is ready when you need it, so the cooking flows smoothly without interruption.
Step 2: Brown Sausage and Sauté Aromatics
- 1 lb italian sausage
- 1 large onion
- 5 cloves garlic
- 1 tsp salt
- 1.5 tsp italian seasoning
- 3.5 cups marinara
In a large skillet over medium-high heat, brown the Italian sausage (with casings removed) and diced onion together, breaking the sausage into small pieces as it cooks, until the meat is no longer pink and onion is softened, about 8-10 minutes.
Add the minced garlic, salt, and Italian seasoning, then cook for 1 minute until fragrant.
Pour in the marinara sauce and simmer for 5-10 minutes to allow the flavors to meld.
I find that simmering the sauce with the sausage for a few minutes really lets the spices penetrate the sauce rather than having them taste one-dimensional.
Step 3: Boil Pasta and Wilt Spinach
- 14.5 oz mostaccioli pasta
- 2.5 cups spinach
- 1/4 tsp red pepper flakes
- sauce mixture from Step 2
While the sauce simmers, bring a large pot of salted water to a boil and cook the mostaccioli pasta 2 minutes less than the package directions to keep it al dente—it will continue cooking in the oven.
Drain the pasta and set aside.
Stir the chopped spinach and red pepper flakes into the sauce from Step 2, cooking until the spinach is wilted, about 2-3 minutes.
The residual heat will soften the spinach without turning it dark and bitter.
Step 4: Mix the Ricotta Filling
- 2 cups mozzarella
- 2 cups ricotta
- 1/4 cup parmesan
- 1 large egg
- Pinch of nutmeg
In a medium bowl, combine the ricotta, 2 cups of freshly shredded mozzarella, 1/4 cup Parmesan, and the egg.
Mix until evenly combined.
I prefer using freshly shredded mozzarella over pre-shredded because it melts much more smoothly and creates a creamier, more cohesive cheese layer without any graininess.
Step 5: Build the Pasta Layers
- cooked pasta from Step 3
- sauce mixture from Step 3
- cheese filling from Step 4
- 2 cups mozzarella
- 1/4 cup parmesan
Spread 1/2 cup of the meat sauce from Step 3 on the bottom of your prepared 9×13 inch baking dish.
Layer half of the cooked pasta over the sauce, then spread half of the cheese mixture from Step 4 over the pasta.
Add half of the remaining sauce (about 1.5 cups) on top.
Layer the rest of the pasta, then the remaining cheese mixture, and finish with the final layer of sauce.
Top the whole dish with the remaining 2 cups mozzarella and 1/4 cup Parmesan.
Step 6: Bake Until Golden and Bubbly
Bake the assembled mostaccioli in your preheated 425°F oven for 15-20 minutes, until the top is bubbly and the cheese is golden brown.
Remove from the oven and let it rest for 5 minutes before serving—this allows the layers to set slightly so each spoonful holds together nicely instead of sliding around on the plate.
Italian Sausage Baked Mostaccioli with Spinach
Ingredients
Method
- Dice the onion into 1/2-inch pieces, mince the garlic, and roughly chop the spinach. While you’re prepping, preheat your oven to 425°F and grease a 9×13 inch baking dish. This prep work ensures everything is ready when you need it, so the cooking flows smoothly without interruption.
- In a large skillet over medium-high heat, brown the Italian sausage (with casings removed) and diced onion together, breaking the sausage into small pieces as it cooks, until the meat is no longer pink and onion is softened, about 8-10 minutes. Add the minced garlic, salt, and Italian seasoning, then cook for 1 minute until fragrant. Pour in the marinara sauce and simmer for 5-10 minutes to allow the flavors to meld. I find that simmering the sauce with the sausage for a few minutes really lets the spices penetrate the sauce rather than having them taste one-dimensional.
- While the sauce simmers, bring a large pot of salted water to a boil and cook the mostaccioli pasta 2 minutes less than the package directions to keep it al dente—it will continue cooking in the oven. Drain the pasta and set aside. Stir the chopped spinach and red pepper flakes into the sauce from Step 2, cooking until the spinach is wilted, about 2-3 minutes. The residual heat will soften the spinach without turning it dark and bitter.
- In a medium bowl, combine the ricotta, 2 cups of freshly shredded mozzarella, 1/4 cup Parmesan, and the egg. Mix until evenly combined. I prefer using freshly shredded mozzarella over pre-shredded because it melts much more smoothly and creates a creamier, more cohesive cheese layer without any graininess.
- Spread 1/2 cup of the meat sauce from Step 3 on the bottom of your prepared 9×13 inch baking dish. Layer half of the cooked pasta over the sauce, then spread half of the cheese mixture from Step 4 over the pasta. Add half of the remaining sauce (about 1.5 cups) on top. Layer the rest of the pasta, then the remaining cheese mixture, and finish with the final layer of sauce. Top the whole dish with the remaining 2 cups mozzarella and 1/4 cup Parmesan.
- Bake the assembled mostaccioli in your preheated 425°F oven for 15-20 minutes, until the top is bubbly and the cheese is golden brown. Remove from the oven and let it rest for 5 minutes before serving—this allows the layers to set slightly so each spoonful holds together nicely instead of sliding around on the plate.