1. Start by preparing your slow cooker insert with butter, rubbing it around the bottom and sides to prevent sticking. I remember Mama Lu saying, “A little care up front saves trouble later.”
2. Place the chicken breasts at the bottom of the slow cooker. Sprinkle with salt, pepper, Italian seasoning, and red pepper flakes if using.
3. Layer the minced garlic and chopped onion over the chicken, letting their aroma weave through the dish as it cooks.
4. Pour in the chicken broth and milk, giving the mixture a gentle stir to combine flavors without disturbing the chicken too much.
5. Add the uncooked penne pasta on top—no need to pre-cook. The liquid will soften it perfectly over time.
6. Cover and cook on low for 3 to 4 hours. Keep an eye after 3 hours, as slow cooker temperatures can vary; the chicken should be tender and the pasta fully cooked but not mushy.
7. Once the pasta and chicken are tender, shred the chicken using two forks right in the slow cooker. This is the moment I think of those flour-dusted afternoons, when shredding chicken was our family’s way of saying “almost ready.”
8. Stir in the shredded cheddar and mozzarella cheeses until melted and gooey, creating a luscious sauce.
9. Taste and adjust seasoning with salt and pepper as needed. Garnish with fresh parsley before serving.

Slow and steady here is the key, much like the patient stirring of Mama Lu’s pot roast gravy that thickened just right after hours of loving attention.