Remove bottoms of asparagus by snapping at the end. Drizzle with oil, sprinkle with salt and pepper and reserve.
Drizzle chicken breast with oil, sprinkle with salt, pepper, and garlic powder and add to the hot grill and cover. Cook for 4-5 minutes, flip, and add asparagus. Continue to cook for another 4-5 minutes or until chicken is cooked through. Allow chicken to rest for a few minutes before slicing.
While chicken and asparagus grill, add balsamic vinegar to a small saucepan and bring to high heat, allow to reduce for 3-4 minutes.
Add reduced balsamic vinegar to yogurt along with mustard. Stir to combine and add salt and pepper to taste.
Add quinoa to two bowls and top with asparagus, sliced chicken, avocado, and tomatoes. Drizzle with dressing and eat!