1. Preheat oven to 400°F (200°C). Slice spaghetti squash in half lengthwise and scoop out seeds.

2. Brush each half with olive oil, season with salt and pepper, and place cut-side down on a baking sheet.

3. Roast for 35–40 minutes until the squash is tender and strands easily separate with a fork.

4. Meanwhile, cook sausage in a skillet over medium heat until browned, about 6–7 minutes.

5. Add diced apple and cook for 2 minutes, then stir in chopped spinach until wilted.

6. Once squash is done, scrape strands lightly with a fork and toss with the sausage mixture inside the shells.

7. Top with shredded pepper jack cheese and broil for 3–4 minutes until melted and bubbly.

8. Serve hot, sprinkled with red pepper flakes if desired.