Pat the fish fillets dry with a paper towel and season both sides with salt and black pepper. Set them aside.

Heat olive oil in a large pot over medium heat. Add the diced onion and sauté for about 3 to 4 minutes, stirring occasionally until softened.

Stir in garlic, ginger, and red curry paste. Cook for 1 minute until the mixture becomes fragrant.

Pour in the coconut milk and broth. Stir to combine and bring to a gentle simmer.

Add the seasoned fish fillets to the simmering liquid. Cover partially and cook for 8 to 10 minutes or until the fish is opaque and flakes easily with a fork.

Stir in the fish sauce and lime juice. Taste and adjust the seasoning with additional salt or lime juice if needed.

Ladle the soup into individual bowls and garnish with chopped cilantro. Serve with lime wedges on the side.