Classic combination found in southern Italy. You can use this on any flaky fish fillets and shrimp too.
2 tablespoons olive oil
1/2 onion, diced
2 cloves garlic, minced
1 tablespoon capers
1 tablespoon caper juice
1 cup cherry tomatoes, halved
1/3 cup pitted, sliced green olives (such as Castelvetrano)
1 teaspoons dried oregano
2 red snapper fillets, or any flaky white fish
sea salt and pepper to taste
1/2 teaspoon red pepper flakes, or more to taste
Preheat oven to 425 degrees F (220 degrees C). In a skillet over medium heat, add the 2 T olive oil and onion; cook until onions begin to turn translucent. Add garlic until fragrant, about 30 seconds. Add capers and caper juice; stir to combine. Then stir in tomatoes and olives, cooking the tomatoes until they begin to collapse, about 3 minutes. Add the oregano. Remove from heat.
Drizzle additional olive oil into a baking dish. Arrange the fish fillets in a single layer. Then sprinkle with sea salt, black pepper and pepper flakes, if desired. Top with the filling and juice from the lemon. Bake until fish is flaky and no longer translucent, about 15 to 20 minutes.