4 boneless, skinless chicken breasts
1 cup basil pesto
6 ounces fresh mozzarella cheese, sliced into 12 pieces
3 tomatoes, thickly sliced
1 pint cherry tomatoes
2 tablespoons extra-virgin olive oil
Kosher salt and freshly ground black pepper
12 ounces spaghetti
2 tablespoons balsamic vinegar
Chopped fresh basil, as needed for finishing
Preheat the oven to 350F. Grease an oven-safe skillet generously with nonstick cooking spray.
Place the chicken breasts in the prepared skillet. Dollop one tablespoon of pesto onto each piece of chicken and spread so it evenly covers the chicken.
Top each chicken breast with 3 mozzarella slices and a few tomato slices. Arrange the cherry tomatoes in the skillet around the chicken. Drizzle with olive oil and season with salt and pepper.
Transfer the skillet to the oven and bake until the cheese is melted, the tomatoes are soft and the chicken is fully cooked, 20 to 22 minutes.
While the chicken cooks, bring a large pot of salted water to a boil. Add the spaghetti and cook until al dente (or according to the package instructions). Drain the pasta, then toss with the remaining pesto.
To serve, divide the pasta among four plates and top each serving with a piece of chicken. Drizzle each plate with 1/2 tablespoon balsamic vinegar and garnish with fresh basil.