Cheesy Beef and Bell Pepper Casserole
Diced peppers folded through browned beef, cheddar melted over the top – 30 minutes
This is a weeknight skillet that finishes in the oven. Ground beef gets a hard brown, then diced red, green, and yellow peppers stay in small cubes so you get a pop of color in every bite. Tomato paste and garlic bind it. Cheddar and mozzarella melt into the gaps.
About 30 minutes start to table. No rice, no pasta. The peppers are the bulk.
Why you’ll love this casserole
- 38g protein per serving – dinner that fills you up
- Only 7g net carbs – peppers instead of pasta
- About 30 minutes, one skillet plus one dish
- Diced peppers stay bright and a little crisp
- Cheddar and mozzarella melt into every scoop
- Reheats clean for lunch boxes
Health notes
- High protein: Lean beef plus a cheddar-mozzarella lid.
- Low carb: Bell peppers for bulk, no rice or noodles.
- Color: Three peppers mean fiber and vitamin C with few carbs.
- Fast: Short oven time keeps the peppers from going mushy.
Key element – dice small, cook just until glossy
Cut the peppers into 1/2-inch cubes so they match the beef. Cook them only until the edges shine, about 3 minutes. If they go limp in the skillet, they turn watery in the oven. You want cubes that still hold their shape under the cheese.
Ingredients
Beef and peppers
- 1 1/2 lb (680g) lean ground beef (90/10)
- 1 small onion, diced
- 1 red bell pepper, diced 1/2-inch
- 1 green bell pepper, diced 1/2-inch
- 1 yellow bell pepper, diced 1/2-inch
- 3 garlic cloves, minced
- 1 Tbsp olive oil
- 2 Tbsp tomato paste
- 1/4 cup beef broth or water
- 1 tsp smoked paprika
- 1 tsp dried oregano
- 1/2 tsp garlic powder
- 3/4 tsp salt + 1/2 tsp black pepper
- Pinch of red pepper flakes (optional)
Cheese lid
- 1 cup shredded sharp cheddar
- 1 cup shredded mozzarella
- Chopped parsley to finish
Swaps
- Turkey: Use ground turkey and add 1 extra Tbsp oil.
- Spicy: Add a diced jalapeno with the peppers.
- Creamy: Stir 2 oz cream cheese into the skillet before you transfer.
- One color: Use 3 of the same pepper if that is what you have.
Instructions
| 1 | Heat the oven. Heat oven to 400 F (205 C). Lightly grease a 9×13-inch glass baking dish. Dice the onion and all three peppers into even 1/2-inch cubes so they cook at the same time. |
| 2 | Brown the beef. In a large skillet over medium-high, heat the oil. Cook the beef until well browned, 6 to 7 minutes. Drain extra fat. Stir in paprika, oregano, garlic powder, salt, pepper, and flakes. |
| 3 | Add the peppers. Stir in onion and diced peppers. Cook 3 minutes until the cubes look glossy but still hold their shape. Add garlic 30 seconds. |
| 4 | Bind and layer. Stir in tomato paste and broth. Simmer 1 minute until thick, not soupy. Spread in the baking dish. Top with cheddar and mozzarella. |
| 5 | Bake and rest. Bake 15 to 18 minutes until the cheese is melted and browned in spots. Rest 4 minutes so the scoop holds. Finish with parsley. |
Pro tips
- Even cubes beat long strips here. You want pepper in every bite, not ribbons.
- The mix should mound on a spoon before it goes in the dish. Thin sauce = watery bake.
- A hot 400 F oven browns the cheese fast so the peppers stay crisp-tender.
- Resting 4 minutes is what lets you lift a clean square.
- Shred your own cheddar. Pre-shredded bags do not melt as smoothly.
Nutrition
| Nutrient | Per serving (1/6) |
|---|---|
| Calories | 410 |
| Protein | 38g |
| Net carbohydrates | 7g |
| Total carbohydrates | 10g |
| Fiber | 3g |
| Total fat | 24g |
| Sodium | 640mg |
Estimates with 90/10 beef and a cheddar-mozzarella lid. Pepper size and cheese brand will shift the numbers.
Variations
Italian night
Add 1 tsp Italian seasoning and finish with extra oregano and a few basil leaves.
Tex-Mex
Swap oregano for cumin and chili powder. Serve with sour cream and lime.
Loaded
Stir in 1/2 cup cauliflower rice with the tomato paste for extra bulk, still low carb.
Meal-prep cups
Divide into 6 ramekins and bake 12 to 14 minutes. Easy lunch boxes.
Storage
| Method | Time | Notes |
|---|---|---|
| Refrigerator | Up to 4 days | Covered; reheat at 350 F or in the microwave |
| Freezer | Up to 2 months | Cool fully, wrap well; thaw overnight |
| Meal prep boxes | Up to 4 days | Drain any extra liquid before packing |
FAQ
Test your knowledge
5 quick questions about this casserole
1. Protein per serving?
2. Net carbs per serving?
3. Oven temperature?
4. How should you cut the peppers?
5. How long do the peppers cook in the skillet?
