1. Season the Snapper: Pat the snapper fillets dry with paper towels. Season both sides with salt and freshly ground black pepper.
2. Prepare the Sauce: In a large frying pan, heat 1 tablespoon of olive oil over medium heat. Add the chopped red onion and cook for 3-4 minutes until it starts to soften. Add the minced garlic and chopped red chilli, cooking for another 1-2 minutes until fragrant.
3. Cook the Tomatoes: Add the chopped tomatoes to the pan and cook for 5 minutes, stirring occasionally, until they start to break down.
4. Add Citrus and Capers: Stir in the orange juice, lime juice, and tomato paste. Bring the mixture to a simmer and cook for 10 minutes until the sauce thickens slightly. Add the capers, parsley, and coriander, stirring to combine.
5. Cook the Snapper: In a separate large frying pan, heat the remaining 1 tablespoon of olive oil over medium-high heat. Add the snapper fillets and cook for 3-4 minutes on each side until the fish is cooked through and flakes easily with a fork.
6. Serve: Place the cooked snapper fillets on a serving platter and spoon the spicy tomato, citrus, and herb sauce over the top. Garnish with lemon wedges and extra fresh herbs if desired.