Preheat oven to 400°. Line a large baking sheet with parchment paper or non stick spray. Set aside.
In a small bowl, mix together balsamic vinegar, honey, garlic and mustard. Set aside.
Cut up chicken breast in bite sized cubes, and spread out on baking sheet.
Cut up peppers and onions. Spread out on baking sheet with chicken.
Season with some salt and pepper.
Drizzle half of your honey balsamic sauce on top of chicken and veggies.(reserving the rest for after its cooked).
Mix everything around until everything is coated and combined. Spread chicken and veggies out evenly.
Bake in preheated oven for 20-25 minutes, or until the chicken is cooked and veggies are tender and starting to brown.
When done, drizzle the rest of honey balsamic sauce over chicken and veggies.
Sprinkle with some fresh chopped up basil.
Enjoy!