Set up your barbecue for direct cooking with a Weber Q Large Frying Pan or hotplate. Please refer to your handbook for further instructions. Preheat your barbecue for barbecuing.
To make the tomato salsa. In a medium bowl, combine the garlic, olive oil, red wine vinegar, brown sugar, salt and pepper. Add the tomatoes, red onion and basil. Toss to combine. Set aside until required.
Lightly oil the barramundi fillets, season with salt and pepper.
Once the barbecue has preheated, adjust the burner(s) to medium. Place the barramundi fillets on the hotplate or in the frying pan, skin side down and cook for 7 minutes.
Turn the fillets and cook for a further 4 to 5 minutes, or until cooked through and starting to flake.
Serve the barramundi fillets with the tomato salsa.