Whisk honey mustard, melted butter, oil, Worcestershire sauce, brown sugar, and garlic powder together in a bowl until well combined. Reserve 2 tablespoons marinade for basting.

Place salmon into a shallow baking dish and pour remaining marinade over top. Cover and refrigerate for 45 minutes.

Preheat the oven's broiler and set the oven rack about 5 inches from the heat source.

Broil salmon in the preheated oven, brushing occasionally with the reserved 2 tablespoon marinade, until fish flakes easily with a fork and marinade has cooked into a glaze, about 12 minutes.