Stuffed spaghetti squash is a ground beef dinner where the squash halves do double duty as both the cooking vessel and the serving bowl. The filling is a straightforward tomato-and-beef mixture with green pepper, red onion, baby carrots, and cheddar on top. It takes about an hour and a half start to finish, most of that hands-off oven time, and uses ingredients most households already have on hand.
Before you start
The single technique that determines whether this dish works is getting the squash properly roasted in the first bake. Undercooked squash won’t release its strands cleanly, and the filling will sit on top rather than nesting into it. Cut the halves as evenly as possible so they cook at the same rate, and make sure the cut side goes face-down on the baking sheet — this traps steam and softens the flesh faster than roasting cut-side up. The second thing worth knowing: add the garlic to the pan after the vegetables have had a few minutes to soften, not at the start. Ground beef filling cooks quickly and garlic goes bitter fast in a hot pan with nothing to protect it.
Ingredient notes
- Spaghetti squash: Two small squashes (roughly 2–2.5 lb each) work better than one large one here — the walls are thicker relative to the cavity, so they hold their shape when filled. Large squash can go mushy.
- Baby carrots: Regular carrots cut into small dice work exactly the same. One medium carrot is a fair substitute for a handful of baby carrots.
- Tomato paste: If you only have a full can and don’t want leftovers, freeze the rest in a tablespoon-sized portions in an ice cube tray — it keeps for months.
- Worcestershire sauce: Soy sauce works as a swap in a pinch. Use about half the amount since it’s saltier.
- Italian seasoning: If you don’t have a blend, a mix of dried oregano and basil in equal parts covers it adequately.
- Cheddar: Any hard cheese that melts — Monterey Jack, mozzarella, Colby — is fine. Skip the fancy aged stuff here; it doesn’t melt as smoothly and costs more for no real gain.
Keeping and reheating
Leftovers keep well in the fridge for up to 4 days in an airtight container. Store the squash halves intact if possible — they reheat more evenly that way. To reheat, cover loosely with foil and warm in a 350°F oven for 15–20 minutes, or microwave on medium power in 90-second bursts until the center hits 165°F. The squash releases more liquid as it sits, so don’t be surprised if the filling looks a bit saucier the next day — it still tastes good. For freezing, scoop the filling out of the squash shells before freezing; the squash itself turns watery and soft after thawing and isn’t worth saving. The beef filling freezes well for up to 3 months. Thaw overnight in the fridge, then reheat in a skillet and serve over freshly roasted squash or rice.
Mistakes to avoid
- Skipping the draining step after browning the beef: Ground beef releases a significant amount of fat as it cooks. If you leave it in the pan, the filling turns greasy and the tomato sauce won’t reduce properly. Tilt the pan and spoon off the excess, or transfer the beef briefly to a paper-towel-lined plate.
- Overfilling the squash halves: It’s tempting to pile the filling high, but too much weight causes the squash walls to collapse when you pick them up to serve. Fill to just level with the rim of the squash.
- Adding cheese too early in the second bake: If the cheddar goes on at the start of the second bake, it browns and dries out before the filling is hot through. Add it in the last 5 minutes only.
- Not checking the internal temperature of the beef filling: The filling needs to reach 160°F (71°C). If you’ve prepped ahead and the beef went into the squash cold from the fridge, budget an extra 10 minutes of oven time and verify with a thermometer before serving.
- Cutting the squash lengthwise unevenly: An uneven cut means one half has a shallow cavity and one has a deep one — they’ll cook at different rates and hold different amounts of filling. Take a moment to find the true center before cutting.
Savoury Stuffed Spaghetti Squash
Ingredients
2 small spaghetti squash
1 pound ground beef (minced beef)
1 small red onion
½ medium green pepper (green capsicum)
10 baby carrots - quartered
4 cloves garlic - minced
1 cup water
14 ounces tomatoes - diced
6 ounces tomato paste
1 tablespoon Worcestershire sauce
1 tablespoon Italian herbs (oregano, rosemary, thyme, and sometimes basil and parsley)
1 pinch salt
1 pinch ground black pepper
¼ cup cheddar cheese - grated
Instructions
- Preheat oven to 350 degrees Fahrenheit. Cut the squash in half lengthwise and remove the seeds. Place cut-side down in a baking dish. Fill the bottom of the dish with water to about 1 inch deep. Bake for 20 to 30 minutes, until squash is softened but not completely cooked.
- While squash is baking, brown ground beef in a large skillet, add onion, green pepper and carrots. Continue cooking until vegetables become tender. Saute garlic and cook for about a minute. Add water, tomatoes, tomato paste, Worcestershire sauce, and Italian Seasoning. Salt and pepper to taste. Let simmer until liquid is evaporated.
- Dump water from your baking dish. Turn squash halves over so they’re cut-side up. Fill cavities with tomato mixture. Bake the squash for about 35 to 40 minutes, until squash is cooked through. Top with cheese and put back in the oven just long enough to melt cheese for about 5 minutes.
Nutrition
Common questions
Can I use ground turkey or chicken instead of ground beef?
Yes, both work well in this filling. Ground poultry must reach an internal temperature of 165°F (74°C) — higher than beef — so make sure the filling is fully cooked through before stuffing the squash. Turkey is slightly leaner than beef, so add a small drizzle of olive oil to the pan when browning to prevent sticking.
How do I know when the spaghetti squash is done in the first bake?
Pierce the skin with a fork — it should go in with light resistance, similar to a baked potato that’s almost done. The strands inside should separate when you drag a fork across them but still have a little firmness. If they’re completely soft and mushy at this stage, the second bake will overcook them.
Can I prep this ahead of time?
You can roast the squash and make the beef filling a day ahead, then refrigerate them separately. When ready to eat, fill the squash halves and bake at 375°F for 25–30 minutes until everything is heated through to 160°F, then add the cheese for the final 5 minutes. This actually makes weeknight assembly very quick.
My squash is very large — do I need to adjust anything?
A large squash (over 3 lb) will need 10–15 extra minutes in the first bake, and you’ll likely need to scale up the filling or it will look sparse in the bigger cavity. The walls on a large squash are also thicker, so check doneness with a fork rather than going by time alone.
Try these next
- Spicy Beef Stuffed Peppers
- Hearty Beef Cauliflower Bake
- Layered Beef Enchilada Casserole
- Savory Stuffed Onion Dolma
