Preheat the oven to 400F. Using a sharp knife, carefully slice the spaghetti squash in half from stem to base. Use a spoon to fully remove the seeds and stringy bits from each half.
Drizzle each half with just a dash of olive oil. Use clean hands or a pastry brush to fully coat the entire squash with oil. Sprinkle the insides with salt and pepper.
Place on a large baking sheet cut side up. Roast at 400 F for 35-40 minutes. The squash is ready when the inside easily shreds with a fork. Taste for texture and add 5 minutes additional time for softer shreds.
To easily shred the squash, use tongs to hold the spaghetti squash in place and use a fork to shred as much as the inside as able.
Filling
In a large skillet over medium heat, add a drizzle of olive oil. Once hot, add the veggie sausage, diced pepper, and diced onion. Sprinkle with salt. Cook until softened and golden, about 6-8 minutes.
Add the minced garlic and continue cooking until aromatic, about 1-2 minutes.
Deglaze the pan with balsamic vinegar. Pour in the marinara sauce and remaining seasonings.
Let simmer over medium-low heat until the spaghetti squash is ready. Add in the shredded spaghetti squash, stirring to combine.
Distribute the spaghetti squash filling between each squash shell. Top with mozzarella cheese.
Reduce oven heat to 350F. Return to the oven to cook until the cheese is melted, about 5-10 minutes. Optionally, once the cheese is melted turn on the broiler until the cheese is bubbly and golden (make sure to keep an eye on the cheese while brioling).
Remove from the oven and garnish with freshly chopped parsley (optional). Enjoy!
Video
Notes
Sausage: I use Gardein Italian sausage slices, but Tofurkey and Field roast also make delicious Italian-style sausage.
Spaghetti squash texture: I cook spaghetti squash to the equivalent of pasta's "al dente". That means it still has a bite and texture to it. This is usually at ~35 minutes. For softer spaghetti squash, continue cooking for an additional 5-10 minutes (40-45 minutes total).
Serving size: The spaghetti squash make a great serving visual, but one size does not fit every appetite. This recipe makes up to 6 servings and can be served on a plate instead of in a boat.
Nutrition facts are an estimation and will vary based on brands and amounts used.