1 spaghetti squash, halved lengthwise and seeded
2 tablespoons vegetable oil
1 onion, chopped
1 clove garlic, minced
1 ½ cups chopped tomatoes
¾ cup crumbled feta cheese
3 tablespoons sliced black olives
2 tablespoons chopped fresh basil
Preheat the oven to 350 degrees F (175 degrees C). Lightly grease a baking sheet.
Place spaghetti squash cut-sides down on the prepared baking sheet. Bake in the preheated oven until a sharp knife can be inserted with only a little resistance, about 30 minutes. Remove squash from oven and set aside to cool enough to be easily handled.
Meanwhile, heat oil in a skillet over medium heat. Cook and stir onion in oil until tender. Add garlic; cook and stir until fragrant, 2 to 3 minutes. Stir in tomatoes and cook until tomatoes are warmed through.
Use a large spoon to scoop the stringy pulp from the squash and place in a medium bowl.
Toss with cooked onion-tomato mixture, feta cheese, olives, and basil. Serve warm.