While the spaghetti squash cooks, make the chili. Drizzle 1 tablespoon olive oil into a large saucepan over medium heat. Add the onions, green peppers, and oregano and cook, stirring occasionally, until tender, about 5 minutes. Add the garlic, chili powder, cumin, and cayenne and cook, stirring constantly, for one minute. Add the tomatoes and beans and stir to combine. Cook until it starts to bubble (be careful, it may splatter because it's so thick) then reduce heat to medium-low and cover. Cook, stirring occasionally, for another 10 minutes, until heated through. Set aside.
When spaghetti squash are done cooking, flip them over. Sprinkle 1/4 cup of the cheese in the bottom of each half. Fill to the top with chili and top each with remaining cheese. Return to oven and bake until cheese is melted and bubbly, 20-25 minutes.
Serve with assorted toppings.
Because spaghetti squash can vary in size, I wrote this recipe so that there will probably be more chili than you can use. Refrigerate or freeze the leftovers for a quick lunch or to top nachos or baked potatoes some other time!
Use a meaty chili (any chili will do!)
Leave off the cheese and other dairy products (or sub vegan products).