Set Up Your Crockpot: Spray the inside of your crockpot with nonstick cooking spray so nothing sticks and cleanup is easy.
Layer Ingredients: Add the halved baby potatoes to the bottom of the crockpot in a solid layer, then place the chicken breasts on top.
Season: In a small bowl, stir together the minced garlic, dried thyme, dried rosemary, salt, and pepper. Scatter it evenly over the chicken and potatoes.
Add Liquid: Pour the chicken broth into the crockpot.
Cook: Cover and cook on low for 6–8 hours or on high for 3–4 hours, until the chicken is cooked through (165°F) and the potatoes are fork-tender.
Cheesy Finish: 30 minutes before serving, sprinkle the Parmesan and mozzarella over the chicken and potatoes. Put the lid back on until the cheese is melted and gooey.
Garnish and Serve: Garnish with fresh parsley and serve hot.