1. Marinate the Chicken:

• Place the chicken breasts in a freezer bag or a shallow dish.
• In a small bowl, whisk together the balsamic vinegar, pesto, honey, pinch of red pepper flakes (if using), kosher salt, and fresh ground black pepper.
• Pour the marinade over the chicken. Seal the bag (pressing out air) or cover the dish. Massage the marinade into the chicken.
• Let the chicken marinate at room temperature for at least 1 hour, or preferably refrigerate for longer (up to overnight) for deeper flavor.

2. Cook the Pasta:

• When ready to cook, bring a large pot of salted water to a rolling boil.
• Add the pasta and cook according to package directions until al dente (tender but still firm to the bite).  
• Important: Reserve about 1/2 cup of the starchy pasta water before draining. Drain the pasta and set aside.

3. Grill the Chicken:

• While the pasta cooks, preheat your grill (outdoor or indoor grill pan) to approximately 400°F (200°C). Clean and oil the grates.  
• Remove the chicken from the marinade, letting excess drip off (discard leftover marinade).
• Place the chicken on the hot grill. Cook for approximately 7-8 minutes per side, flipping once. Cooking time will vary depending on the thickness of the chicken breasts. Ensure the internal temperature reaches 165°F (74°C).
• Remove the grilled chicken from the grill and transfer it to a clean cutting board. Let it rest for at least 5 minutes before slicing. This is crucial for keeping it juicy.

4. Make the Tomato Basil Pasta Sauce:

• While the chicken rests, heat the 2 tablespoons of olive oil in a large skillet over medium heat.
• Add the minced or grated garlic and the pinch of red pepper flakes (if using). Sauté for about 30-60 seconds until fragrant – be careful not to burn the garlic.
• Add the halved cherry tomatoes to the skillet. Cook, stirring occasionally, for about 3-5 minutes, until the tomatoes just begin to soften and burst slightly, releasing their juices.
• Stir in the chopped fresh basil leaves, kosher salt, and fresh ground black pepper to taste.

5. Combine Pasta and Sauce:

• Add the drained cooked pasta to the skillet with the tomato-basil mixture.
• Add the 3 tablespoons of shredded Parmesan cheese.
• Toss everything together well to coat the pasta. If the pasta seems dry, add a splash (1-2 tablespoons at a time) of the reserved starchy pasta water to help create a light sauce.

6. Slice Chicken and Serve:

• Slice the rested grilled chicken thinly against the grain.
• Serve the Tomato Basil Pasta in bowls or on plates. Top the pasta generously with the sliced Balsamic Grilled Chicken.
• Optional Garnishes: Drizzle with balsamic glaze and sprinkle with extra chopped fresh basil and more Parmesan cheese, if desired. Serve immediately.