Preheat oven to 425°F (220°C).

Toss halved tomatoes with 1 tbsp olive oil, a pinch of salt, and pepper on a rimmed baking sheet. Roast for 15–18 minutes until edges caramelize.

Tip: Line the tray with foil for easy cleanup and a slightly faster roast.

Bring a large pot of salted water to a boil and cook pasta to al dente according to package instructions. Reserve 1 cup pasta water, then drain.

Tip: Al dente pasta holds sauce better; test 1–2 minutes before the package time.

While pasta boils, heat 2 tbsp olive oil in a large skillet over medium-high heat. Season chicken with salt and pepper; sear until cooked through (about 5–7 minutes). Remove and set aside.

Tip: Don’t overcrowd the pan—work in batches if needed to get a golden crust.

Lower heat to medium. Add a splash of reserved pasta water to the skillet, stir in pesto, then fold in cooked pasta, roasted tomatoes, and chicken. If sauce is too thick, add more pasta water a tablespoon at a time.

Tip: Adding pasta water helps emulsify pesto into a silky sauce—starch + oil = magic.

Remove from heat. Stir in grated Parmesan (or nutritional yeast), torn basil, lemon zest, and toasted nuts if using. Adjust salt and pepper.

Want extra tricks for weeknight dinners? If you want make-ahead tips, see honey mustard chicken pasta salad and adapt the storage strategies.