Preheat an indoor or outdoor grill to medium-high. Lightly brush the prawns with 1 Tbsp. of the oil and then set aside. Heat the remaining oil in a non-stick skillet or wok set over medium-high. Add the bell pepper and carrot and stir-fry 1 minute. Add the bok choy, snow peas, ginger, garlic and onions and stir-fry 1 minute more. Mix in 1/4 cup of the sweet chili sauce and the water, reduce the heat to low, and reserve until the prawns are cooked. Grill the prawns 1 to 2 minutes per side. Brush with the remaining sweet chili sauce. Divide the stir-fry between 2 plates. Set 2 prawns skewers on each plate and serve.
Note: Thai-style sweet chili sauce is available in the Asian foods aisle. Raw and ready-to-cook prawn skewers are available in the seafood department.