- 1 tablespoon olive oil
- 1 red onion, chopped
- 2 small yellow squash, cut into 1/2-inch pieces
- 2 cloves garlic, chopped
- 1 jalapeño, seeded and thinly sliced
- kosher salt and black pepper
- 1 28-ounce can diced tomatoes
- 4 6-ounce pieces skinless halibut fillet
- Heat the oil in a large skillet over medium heat. Add the onion and cook, stirring occasionally, until soft, 6 to 8 minutes.
- Add the squash, garlic, jalapeño, ½ teaspoon salt, and ¼ teaspoon pepper. Cook, stirring occasionally, until the squash begins to soften, 3 to 4 minutes.
- Stir in the tomatoes and their liquid. Season the halibut with ½ teaspoon salt and ¼ teaspoon pepper and nestle it among the vegetables.
- Cover and simmer over medium-low heat until the halibut is opaque throughout and beginning to flake, 10 to 12 minutes.