1) Heat the oil in a small saucepan over medium heat. Add the shallots and garlic and cook until soft. Stir in the hoisin, ketchup, honey, sambal oelek, sesame seeds, soy sauce and fish sauce and cook for 5 minutes.
2) Remove from the heat, stir in the vinegar and season with salt and pepper, to taste.
For the fish:
1) Heat the griddle to high. Brush the salmon on both sides with oil and season with salt and pepper, to taste. Griddle until golden brown and slightly charred on both sides. Cook to medium-well doneness, brushing with the sauce every minute or so.
2) Remove the salmon from grill to a plate and brush with more sauce. Transfer the fish to a serving platter and let rest for 5 minutes. Garnish with coriander and serve.