Prepare the Skewers: If using wooden skewers, soak them in water to prevent burning on the BBQ.
Prepare the Vegetables: Finely slice the sweet potato and beetroot. Cut the mushrooms into long, thin strips. In a bowl, mix the sliced vegetables with 1 tbsp of oil, a pinch of salt, and 2 tbsp of tamari or soy sauce.
Make the Dressing: Peel and finely dice the garlic. In a mug, combine the diced garlic with the rest of the dressing ingredients and mix well.
Skewer the Vegetables: Thread the marinated vegetables onto the soaked skewers, alternating between sweet potato, beetroot, and mushroom slices. Repeat the pattern, folding some of the larger pieces of vegetables over and back on themselves to create an interesting shapes. You should get at least 5-6 filled vegetable skewers.
Brush with Dressing: Using a pastry brush, generously coat the vegetable skewers with the prepared dressing.
Barbecue: Cook the skewers on a barbecue over medium heat or on an open flame, preferably on the embers, to cook the sweet potato before charring. Brush the skewers with more dressing midway through cooking to encourage caramelization.
Serve: Serve with your favourite salad for an easy and delicious barbecue dish.