Whisk together oil and soya sauce. Brush over entire surface of both sides of the chicken wings. Arrange wings main skin side up in oven safe baking dish.
Mix together brown sugar, celery seed and chili powder. Season with salt. Sprinkle half of mixture evenly over wings.
Broil wings on the centre rack, watching closely so they don't burn too much. You want them to blacken as evenly as possible. Move wings around to maximize blackening areas.
Turn wings over once tops are well blackened, sprinkle remaining sugar and spice mix over top. Return to broiler and blacken other side.
Adjust oven to 350° set to bake. Mix together tomato soup and vinegar. Add Sririacha sauce for extra heat if desired. Heat mixture in microwave the prevent cracking baking dish. Turn wings so best skin side is facing up. Pour sauce evenly over top, stirring oil and spices from the bottom into the sauce and spooning over wings.
Bake uncovered in centre of the oven for about 40 minutes until sauce is thickening and bubbling. Spoon sauce over top at halfway point to ensure pieces are well coated.
Serve with rice and garnish with fresh chives if desired.