Prepare the Chicken. Place the chicken breasts in the bottom of your crock pot. Season with salt, pepper, and minced garlic.
Add the Sauce Ingredients. Pour the heavy cream and chicken broth over the chicken. Add butter and freshly grated Parmesan cheese.
Cook on Low. Cover and cook on low for 4-5 hours until the chicken is fully cooked and tender.
Shred the Chicken. Remove the chicken from the crock pot and shred it using two forks. Return the shredded chicken to the sauce.
Cook the Pasta. Add the fettuccine to the crock pot, ensuring it is submerged in the sauce. Cover and cook for an additional 30 minutes or until the pasta is tender.
Serve. Once the pasta is cooked, stir everything together. Garnish with fresh parsley and more Parmesan if desired. Serve warm!