1. Preheat oven to 400 degrees

2. Arrange the asparagus on a baking sheet.  Coat with cooking spray, and season with salt and pepper.

3.Bake asparagus 12 minutes in the preheated oven, or until tender.

4.Melt the butter in a saucepan over medium heat.  Remove from heat, and stir in soy sauce and balsamic vinegar.  Pour over the baked asparagus to serve.