Preheat your oven to 400°F (200°C) and lightly grease a 9x13-inch baking dish.

In a large pot, bring salted water to a rolling boil. Add penne or rigatoni pasta and cook for 2 minutes less than package instructions, then drain.

In a skillet, heat olive oil over medium-high heat. Add seasoned chicken breasts, cook until golden brown and cooked through, about 5–6 minutes.

Melt unsalted butter in the same skillet. Add minced garlic and sauté for 30 seconds. Pour in heavy cream and whole milk, simmer for 2-3 minutes.

Stir in basil pesto and grated Parmesan cheese until the sauce is smooth.

Return sliced chicken to the skillet with drained pasta. Add baby spinach, if using, and mix gently.

Transfer the mixture to the prepared baking dish, top with shredded mozzarella and more Parmesan.

Bake uncovered for about 20–25 minutes until cheese is melted and golden.

Let rest for 5 minutes before serving. Enjoy with a side salad or crusty bread!