ciabatta roll or french bread
12 oz boneless, skinless chicken breasts
1 pint grape tomatoes
¾ oz Parmesan
3¾ oz mozzarella
garlic
1 TBL butter
balsamic 
sugar
salt & pepper
olive oil

1. Prep ingredients

Preheat broiler with top rack 6 inches from heat source. Set 1 tablespoon butter in a small bowl to soften at room temperature until step 5. Finely chop 1 teaspoon garlic. Coarsely grate mozzarella and finely grate Parmesan, keeping separate. Halve grape tomatoes.

2. Prep broth mixture

In a liquid measuring cup, stir to combine  ½ cup water, 6 tablespoons vinegar, and 1 tablespoon sugar; set aside until step 4.

3. Sear chicken

Pat chicken dry and pound to an even ½-inch thickness, if desired. Season all over with salt and pepper. Heat 1 tablespoon oil in a medium ovenproof skillet over medium-high. Add chicken and cook until browned, flipping once, about 2 minutes per side (chicken will not be cooked through). Transfer to a plate.

4. Make sauce & broil

Add broth mixture to same skillet. Cook over medium-high, scraping up any browned bits, until reduced to ¼ cup, 2–3 minutes. Add chicken back to skillet along with the halved tomatoes. Broil on top oven rack until tomatoes blister and chicken is cooked through, 2–3 minutes (watch closely as broilers vary).

5. Make garlic butter

Meanwhile, mix chopped garlic and half of the Parmesan into the softened butter; season with salt and pepper. Split roll, if necessary. Spread garlic butter on cut sides of roll; place on a piece of foil. Broil on top oven rack until golden and toasted, 1–2 minutes (watch closely).

6. Finish chicken & serve

Pick basil leaves from stems; discard stems. Sprinkle mozzarella over chicken. Broil on top oven rack until cheese is melted and browned in spots, 1–2 minutes (watch closely). Top with basil leaves, and serve with remaining Parmesan and garlic bread alongside. Enjoy!