In a large bowl combine burger ingredients. Make 6 mounds of mixture into 4 ounces each. DO NOT OVERWORK. Form into patties and refrigerate. Dice 1 mango, shred cabbages and carrots for coleslaw and in a medium bowl combine all coleslaw ingredients, refrigerate.
In a small bowl combine the sweet chili mayo ingredients, refrigerate. Preheat grill on high, cover and heat until hot, about 20 minutes. Peel, pit and slice 3 mangoes into 1/4 inch thick slices. Place patties on grill uncovered 3 minutes, turn burger 1/4 turn for nice grill marks for 1 minute. Flip patties and continue cooking until internal temperature is 135 degrees F. Grill 6 mango slices and brush buns with olive oil and grill to a nice golden brown.
BUILDING YOUR BURGER
On top and bottom bun spread 1 tablespoon on each of sweet chili mayo. Put patty on bottom bun next, top with 1 tablespoon scallions. Next put 1/2 Cup coleslaw and place a grilled mango slice, then top bun and serve.