Cut the chicken breast into 1-inch pieces for quick and even cooking.

Melt the butter in a deep skillet over medium heat. Add the chicken and cook until lightly browned.

Add minced garlic to the skillet and sauté for another minute until fragrant.

Pour in the uncooked pasta and chicken broth. Stir to scrape up any browned bits from the bottom of the skillet.

Cover the skillet, bring the broth to a boil, then reduce heat to medium-low. Let the pasta simmer for about 8 minutes, stirring briefly every 2 minutes to prevent sticking.

Once the pasta is tender and the broth mostly absorbed, stir in the milk, cream cheese (cut into chunks), and pesto. Continue cooking until the sauce is smooth and creamy.

Add the grated Parmesan, spinach, and sun-dried tomatoes. Cook until the spinach wilts, then remove from heat.

Top with freshly cracked pepper and a pinch of crushed red pepper before serving.