Heat 2 tablespoons of olive oil in a skillet over medium heat.
4 tbsp. olive oil
Add the garlic, onion, and red pepper flakes to the skillet; cook for 2 to 3 minutes.
3 garlic cloves, ½ red onion, ½ tsp. crushed red pepper flakes
Add the cherry tomatoes to the skillet and cook for 2 to 3 minutes more.
2 cups cherry tomatoes
Pour in the white wine and bring to a light boil. Stir in the basil, lemon juice, and lemon zest, then season to taste.
½ cup fresh basil, 2 tbsp. fresh lemon juice, Zest from 1 lemon, ¼ cup dry white wine
Lower heat to a simmer and cook for 8 to 10 minutes.
Season the fish to taste with salt and pepper.
Sea salt and freshly ground black pepper
Heat the remaining olive oil in a new skillet over medium heat.
Cook the cod for 4 to 5 minutes per side or until cooked through.
4 fresh cod fillets
Serve the cod topped with the tomato-basil relish.