Preheat oven to 400 degrees, line a baking sheet with foil. spray with cooking spray, and set aside.
Add olive oil to a medium saucepan over medium heat and cook the garlic until tender and fragrant, about 2-3 minutes. Add the honey, balsamic vinegar, Dijon mustard, salt and pepper, to taste. Simmer for about 3 minutes until it slightly starts to thicken, then remove from the heat and divide in half between two small bowls. You will use one for brushing the salmon before baking, and one for serving.
Place the salmon fillets on the prepared baking sheet, skin side down if they have the skin still on. Using one of the bowls of sauce, brush the sauce over the tops of the salmon, generously.
Bake for about 10-12 minutes, depending on the thickness of the fillets, until flesh flakes easily with a fork. Spoon glaze from the second bowl of sauce over the top, and serve with your favorite sides!