3 cups thinly sliced mixed summer squash (we used yellow summer squash and zuccini but you can really use anything you have locally or prefer)
1 tablespoon fresh thyme leaves
1 tablespoon capers, drained and rinsed
3 tablespoons olive oil
Kosher salt and freshly ground pepper
4 cocktail tomatoes, thinly sliced
Preheat oven to 400°F. Place sliced squash, thyme, and capers in a 9-by-13-inch baking dish; drizzle with 2 tablespoons oil and season with salt and pepper.
Season halibut with salt and pepper on both sides and arrange over squashes. Add tomatoes slices on top of and around the halibut. Drizzle fish and tomatoes with remaining 1 tablespoon oil. Cover with foil and bake 15 minutes.
Remove foil and continue to bake until fish is opaque and squashes are tender, about 10 more minutes.