Creating One Pan Balsamic Chicken is simple if you follow these easy steps:

1. Preheat the Oven: Preheat your oven to 400°F (200°C).
2. Prepare the Chicken: Season the chicken breasts with salt and pepper on both sides.
3. Sear the Chicken: In a large oven-safe skillet, heat the olive oil over medium-high heat. Add the chicken breasts and sear on each side for about 4-5 minutes until golden brown.
4. Add Garlic: Add the minced garlic to the pan and cook for an additional minute, stirring constantly to avoid burning.
5. Add Veggies: Put the cherry tomatoes and sliced red onion around the chicken in the skillet.
6. Prepare Balsamic Glaze: Pour the balsamic vinegar over the chicken and vegetables.
7. Transfer to Oven: Place the skillet in the preheated oven and bake for 20-25 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
8. Add Spinach: In the last 5 minutes of cooking, add the fresh spinach to the skillet. Stir to combine and allow it to wilt.
9. Garnish: Once cooked, remove the skillet from the oven and garnish with fresh basil, if desired.

The steps are straightforward, ensuring even novice cooks can create this dish with confidence.