Place an oven rack on one of the middle shelves. Preheat the oven to 425 degrees F and line a large baking sheet with aluminum foil. Lightly grease the baking sheet with olive oil.
Place the wings in a large bowl and toss with the olive oil. Spread in a single layer on the baking sheet and sprinkle the salt on top (I don't actually measure the salt; I just aim for a very light coating on each wing to enhance the flavor). Bake for 50 minutes.
While the chicken is cooking, prepare the sauce. In a medium-sized bowl, combine the hoisin sauce, toasted sesame oil, and soy sauce. Set aside.
When the wings are done, carefully remove the baking sheet. Move the oven wrack to one of the top shelves and turn the broiler on low.
Baste the wings with the sauce and broil them until the sauce is bubbly and cooked on, approximately 3-4 minutes.
If using, sprinkle sesame seeds and scallions on top before serving.