For the sauce:
1 1/4 teaspoons sugar
1/4 teaspoon black pepper
2 tablespoons oyster sauce
2 tablespoons light soy sauce
2 1/2 tablespoons canola oil
3 garlic cloves, minced
2-inch piece fresh ginger, peeled and finely shredded
3 scallions, green part only, chopped

For the steamed salmon
1 scallion, white part only, cut lengthwise into strips
1 1/4 pounds salmon fillet, cut crosswise into two pieces
4 sprigs cilantro