Preheat oven to 400 degrees F. Line a baking sheet with aluminum foil (avoid parchment paper), then coat with non-stick cooking spray.
In a small skillet, heat the olive oil over medium heat. Add the garlic and cook until fragrant and beginning to brown, about 2 minutes, watching carefully so that it does not burn.
Add the balsamic vinegar, honey, mustard, salt, and pepper. Whisk and simmer until the mixture thickens; about 4 minutes.
Place salmon skin-side down on the prepared baking sheet. Brush liberally with the glaze.
Bake for 5 minutes and then remove from the oven.
Baste with the glaze, then bake 5 to 10 additional minutes, until the fish flakes easily with a fork and is cooked through.
Sprinkle with chopped parsley and serve.
Notes
TO STORE: Leftover balsamic glazed salmon may be stored in the refrigerator for up to 3 days.
TO REHEAT: For best results, warm the salmon in a 350 degree F oven until heated through.
TO FREEZE: Balsamic glazed salmon may be stored in the freezer for up to 3 months. Defrost overnight in the fridge before warming.