If your chicken breasts are uneven, place each between plastic wrap and gently pound with a meat mallet to an even thickness.
Prepare 1 cup of the Balsamic Lemon Pepper Chicken Marinade according to the referenced recipe (about 1/4 cup balsamic vinegar, 2 tbsp olive oil, 1 tsp lemon juice, 1 tbsp honey, 1/2 tsp kosher salt, 1/2 tsp lemon-pepper seasoning) or use a prepared marinade.
Place the chicken breasts and the marinade in a resealable bag or shallow container, seal, and refrigerate to marinate for 30–60 minutes (up to 2 hours if desired).
When ready to bake, preheat the oven to 450°F (230°C) and move a rack to the middle position.
Remove the chicken from the marinade and arrange the breasts in a single layer in a 9x13-inch baking dish.
Pour 1 tablespoon melted unsalted butter evenly over the chicken, then drizzle any remaining marinade from the bag over the breasts.
Bake uncovered for 15–18 minutes, or until the chicken is cooked through and an instant-read thermometer inserted into the thickest part registers 165°F (74°C).
Remove the dish from the oven and let the chicken rest in the pan for 10 minutes before slicing and serving.