Place tomato and onion mix in small barbecue cast iron pot, add chutney and garlic.
Place pot on barbeque and simmer for 3 minutes. Season with salt and pepper.

Combine BBQ sauce and mustard to create basting for Burgers.

Grill the Traditional Burgers on the barbeque for 8 minutes, or until cooked through, basting and turning regularly.

Slice the buns in half, lightly brush with olive oil, toast lightly on the barbeque.
Assemble the burger: Layer with relish, sliced tomato and watercress. Add the Burgers, gherkins, red onion and more relish.