Monterey Spaghetti
If you love cozy, creamy pasta casseroles with a crunchy top, this Monterey Spaghetti will be a new favorite in your weeknight rotation. It’s cheesy, comforting, and easy to throw together with pantry-friendly ingredients. The dish layers tender spaghetti with a rich, creamy cheese mixture, flecks of spinach for color and balance, and a golden crown of crispy fried onions for texture. Whether you’re feeding family or bringing a potluck contribution, this recipe hits all the right notes: saucy, satisfying, and simple to prep.
Why you’ll love this version
Think of this as a cross between a baked macaroni and cheese and a spinach casserole. The combination of Monterey Jack and Parmesan gives a mellow, melty base with a savory bite, while ricotta and sour cream add silkiness and body. An egg binds everything so the casserole slices cleanly, and garlic powder plus salt and pepper keep the flavors straightforward and homey. The frozen chopped spinach is an easy way to add vegetables without fuss, and the crispy fried onions provide a contrasting crunch that makes every bite more interesting.
Ingredients
- 8 ounces spaghetti
- 2 cups Monterey Jack cheese, shredded
- 1 cup Parmesan cheese, shredded and divided
- 1 cup sour cream
- ½ cup ricotta cheese
- 1 large egg
- 1 teaspoon salt
- ½ teaspoon pepper
- 1 teaspoon garlic powder
- 10 ounces frozen chopped spinach, thawed and drained
- 6 ounces crispy fried onions, divided
Equipment
- Large pot for boiling pasta
- Colander
- Mixing bowl
- 9×13-inch (or similar) baking dish
- Spoon or spatula
- Measuring cups and spoons
Notes before you start
Be sure to fully thaw and squeeze excess moisture from the frozen chopped spinach. Any extra water will thin the cheesy filling and make the casserole less cohesive. Also, shred the Monterey Jack and Parmesan if they’re not pre-shredded; freshly shredded cheese melts more smoothly. Keep ½ cup of the Parmesan set aside to sprinkle on top before baking for a savory, golden finish.
Step-by-step directions
- Preheat your oven to 350°F (175°C) so it’s ready when the casserole is assembled.
- Bring a large pot of salted water to a boil. Add 8 ounces spaghetti and cook according to package directions until just al dente. Drain the spaghetti well in a colander and immediately return it to the pot or a large mixing bowl.
- While the pasta cooks, make sure the 10 ounces frozen chopped spinach is fully thawed and thoroughly drained. Squeeze out as much liquid as you can using clean hands or a kitchen towel. This prevents a watery casserole.
- In a large mixing bowl, combine 2 cups shredded Monterey Jack cheese, 1 cup shredded Parmesan cheese, 1 cup sour cream, ½ cup ricotta cheese, 1 large egg, 1 teaspoon salt, ½ teaspoon pepper, and 1 teaspoon garlic powder. Mix until smooth and evenly combined.
- Add the drained chopped spinach to the cheese mixture and stir until the spinach is evenly distributed throughout the filling.
- Fold the cooked, drained spaghetti into the cheese-and-spinach mixture. Toss gently but thoroughly so every strand is coated with the creamy mixture.
- Transfer the coated spaghetti into a lightly greased 9×13-inch baking dish, spreading it out evenly so the top is level.
- Reserve ½ cup of the shredded Parmesan and set it aside. Sprinkle that reserved Parmesan evenly over the top of the assembled casserole.
- Take the 6 ounces crispy fried onions and divide them into two portions. Scatter half of the onions over the Parmesan layer, pressing very lightly so they adhere.
- Place the baking dish in the preheated oven and bake at 350°F (175°C) for 20–25 minutes, or until the center is set, the cheese is bubbly, and the top is golden.
- Five minutes before the bake time is finished, remove the casserole from the oven and sprinkle the remaining half of the crispy fried onions over the top for extra crunch, then return to the oven for the remaining time.
- When done, remove the casserole from the oven and let it rest for 5–10 minutes. This resting period helps the casserole set and makes it easier to serve neat slices.
- Scoop and serve warm. Leftovers keep well in the refrigerator for up to 3 days and reheat nicely in the oven or a microwave.
Troubleshooting and tips
- If the top browns too quickly, tent the dish loosely with foil during the last 10 minutes of baking.
- For a lighter touch, use low-fat ricotta and sour cream, but the texture will be slightly less rich.
- Make sure to squeeze the spinach thoroughly; even a little extra moisture can make the casserole runny.
- To make this ahead, assemble the casserole and refrigerate, covered, for up to 24 hours before baking. Add a few extra minutes to the bake time if chilled straight from the fridge.
- For a more pronounced garlic flavor, add ½ teaspoon onion powder or 1 minced garlic clove to the cheese mixture, if desired.
Serving suggestions
This Monterey Spaghetti pairs beautifully with a simple green salad dressed with a bright vinaigrette to cut through the richness. A side of roasted cherry tomatoes or steamed green beans also complements the creamy texture. For a heartier meal, serve with grilled chicken or pan-seared fish alongside.
Make-ahead and storage
You can assemble the Monterey Spaghetti up to a day in advance. Cover tightly and refrigerate; when ready to bake, remove from the fridge and let sit at room temperature for 15–20 minutes, then bake as directed, adding a few extra minutes if necessary. Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in a 350°F (175°C) oven until warmed through, or microwave individual portions until hot.
Flavor variations
- Add a pinch of red pepper flakes to the cheese mixture for a gentle heat.
- Stir in ½ cup cooked, crumbled turkey sausage or shredded chicken for extra protein while keeping to simple, widely available ingredients.
- Swap half the Monterey Jack for sharp cheddar if you prefer a more pronounced cheese flavor.
Why the crunchy onions work
The crispy fried onions are a small but crucial element. They add textural contrast to the creamy interior and a toasted-onion flavor that makes the dish feel complete. Sprinkling half the onions before baking helps them adhere and toast slightly, while adding the rest near the end preserves crunch. That double approach gives you a reliably textured top every time.
Nutrition snapshot
This casserole is indulgent but satisfying, offering a balance of carbohydrates, dairy-based protein, and some greens thanks to the spinach. To lighten the dish, choose reduced-fat dairy versions and add extra spinach or another vegetable to boost fiber and nutrients.
Final thoughts
Monterey Spaghetti is a comforting casserole that’s both nostalgic and effortlessly modern. Its creamy interior, mild melty cheeses, and crunchy topping make it a crowd-pleaser for family dinners and gatherings alike. With straightforward ingredients and a baking time that lets you focus on sides or company, this dish earns a permanent spot in the rotation for anyone who appreciates simple, satisfying food.
Printable recipe
Ingredients: 8 ounces spaghetti; 2 cups Monterey Jack cheese, shredded; 1 cup Parmesan cheese, shredded and divided; 1 cup sour cream; ½ cup ricotta cheese; 1 large egg; 1 teaspoon salt; ½ teaspoon pepper; 1 teaspoon garlic powder; 10 ounces frozen chopped spinach, thawed and drained; 6 ounces crispy fried onions, divided.
Directions: Follow the step-by-step instructions above to cook the pasta, drain and drain the spinach, combine the cheeses, sour cream, ricotta, egg, and seasonings; fold in the pasta and spinach; transfer to a baking dish; top with reserved Parmesan and half the crispy fried onions; bake at 350°F (175°C) until bubbly and golden (20–25 minutes), adding the remaining onions near the end; rest 5–10 minutes before serving.
Monterey Spaghetti
Ingredients
Equipment
Method
- Preheat the oven to 350°F (175°C) and spray a 9x13-inch baking dish with cooking spray.
- Break the 8 ounces of spaghetti in half and cook in a large pot of boiling salted water according to package directions until al dente; drain well.
- In a large mixing bowl, whisk together 2 cups shredded Monterey Jack, 1/2 cup of the shredded Parmesan (reserve the rest), 1 cup sour cream, 1/2 cup ricotta, 1 large egg, 1 teaspoon salt, 1/2 teaspoon pepper, and 1 teaspoon garlic powder until smooth.
- Fold the drained 10 ounces chopped spinach, about 3 ounces of the crispy fried onions, and the cooked spaghetti into the cheese mixture until evenly combined.
- Transfer the mixture to the prepared baking dish, cover with foil, and bake for 30 minutes.
- Remove the foil, sprinkle the remaining crispy fried onions and the reserved Parmesan on top, and bake uncovered 5–8 minutes more until the top is golden and crispy.
- Let the casserole rest at least 5 minutes before serving.
Notes
- Drain spinach thoroughly to avoid a watery casserole.
- Reserve some Parmesan for the topping for best browning.
- Let the dish rest so it sets and is easier to serve.
