One Pan Baked Halibut w/ Cherry Tomatoes

• 1 quart cherry tomatoes
• 1 onion sliced pole to pole
• 4 cloves garlic minced
• 1-2 ripe bell peppers sliced thinly, or equivalent in banana peppers
• 24 ounces whitefish fillets such as halibut or haddock, cut into 4 6-ounce pieces
• 1 Tablespoon olive oil approximate, for brushing
• salt pepper
• Chopped fresh basil or parsley for serving

Dressing:

• 1 Tablespoon capers
• 1 teaspoon honey
• 1 teaspoon salt or to taste
• ½ teaspoon black pepper or to taste
• 3 Tablespoons olive oil
• 2 Tablespoons red wine vinegar