A cozy, smart-carb spin on a classic comfort food favorite! Instead of traditional potatoes, whole butternut squash is roasted plain with garlic and red onion until tender, scooped out, and mashed with roasted garlic, mozzarella, fresh thyme, and seasonings to form a creamy, golden topping. Layered over a savory, high-protein beef and vegetable filling, this double-baked casserole is rich, hearty, and packed with wholesome goodness.
Prep time: 20 mins
Cook time: 50 mins
Yield: 4–6 servings
Ingredients
Butternut Squash Topping
1 large butternut squash, halved and seeded (roasted plain with a pinch of pepper)
Whole heads of garlic (for roasting)
1/2 red onion, sliced (roasted with the squash)
1 tsp fresh thyme leaves (added during mashing)
1/2 tsp garlic powder (added during mashing)
1/2 tsp onion powder (added during mashing)
1/2 cup shredded mozzarella cheese (added during mashing)
Olive oil, salt, and black pepper (for roasting)
Savory Beef & Veggie Filling
1 lb extra-lean ground beef
1 medium onion, finely diced
1/2 cup diced carrots (or leftover squash pieces)
1 cup frozen peas
Fresh thyme sprigs
1 tsp garlic powder
1 tsp onion powder
1/2 tsp paprika
Salt and black pepper, to taste
1/2 cup beef broth or water (for simmering)
Step-by-Step Instructions
Roast the Squash & Garlic: Preheat your oven to 400°F (200°C). Cut the butternut squash in half and score the flesh in a crosshatch pattern. Place cut-side up on a baking sheet alongside whole heads of garlic (top sliced off) and halves of red onion. Drizzle lightly with olive oil and a pinch of black pepper (leaving out herbs/spices so they don't burn during the long roast). Roast for 35–40 minutes until fork-tender and caramelized.
Make the Filling: While the squash roasts, heat a large pot or Dutch oven over medium heat. Add diced onion and carrots, sautéing until soft. Add the ground beef, breaking it apart with a wooden spoon, and season with garlic powder, onion powder, paprika, salt, pepper, and fresh thyme. Cook until the beef is fully browned. Stir in the frozen peas and a splash of beef broth, simmering for a few minutes until well combined. Transfer the filling into a baking dish.
Mash & Season the Squash Topping: Scoop out the roasted butternut squash flesh into a large bowl. Squeeze the soft, caramelized roasted garlic cloves out of their skins right into the bowl. Add the shredded mozzarella cheese, fresh thyme, garlic powder, onion powder, salt, and pepper. Mash everything together until smooth and creamy.
Assemble & Double-Bake: Scoop the seasoned mashed butternut squash topping evenly over the beef and vegetable filling in your baking dish. Use a fork or spoon to create ridges across the top for a golden, crispy finish when baked.
Bake: Place the baking dish back in the oven at 400°F (200°C) for 15–20 minutes, then broil for the last 2–3 minutes until the top is golden and bubbling. Slice, serve warm, and enjoy!