Preheat the oven to 375 F and grease an 8x8" baking dish.

To make the teriyaki sauce, combine the ingredients in a small pot and whisk well. Heat over medium-low heat for 4-5 minutes or until thick. If a thicker sauce is desired, combine about 1-2 tsp of arrowroot starch with chicken broth and add it to the sauce to thicken further. If a thinner sauce is desired, add a splash of chicken broth to thin out the sauce. Set aside.

Soak the ramen in hot water for about 15 min or until soft. Separate with tongs and strain.

Add the ramen to the baking dish along with the veggies, chicken breast, salt and pepper, and teriyaki sauce (reserving about 3-4 tbsp of the sauce on the side). Toss to coat.

Bake in the oven for about 35 min, tossing halfway through. Chicken should be 165 F.

Serve topped the reserved teriyaki sauce and with green onion.