Arrange asparagus in a single layer on a baking sheet; coat with cooking spray. Sprinkle with salt and pepper. Bake for 12 minutes or until tender.
Melt butter in small skillet over medium heat; cook for 3 minutes or until lightly browned, shaking pan occasionally. Remove from heat; stir in soy sauce and vinegar. Drizzle over the asparagus, tossing well to coat. Serve immediately.
Notes
If preparing this recipe as gluten free, just be sure to use a brand of soy sauce that is designated as GF.