Slice potatoes into quarters and layer on one half of the bottom of the slow cooker. On the other half, add the baby carrots. Lay chicken, breast side up, on top of vegetables.
Sprinkle paprika all over the top of the bird. Sprinkle with salt and pepper to taste.
In a small bowl, mix together butter, rosemary, thyme, and garlic.
Stuff the inside of the bird with lemon (if desired) and onion quarters. If using lemon, you can reserve slices for the top as well.
Spread herb butter all over the top of the chicken as well. Add extra sprig of rosemary and thyme and any extra lemon slices (if desired) to the top.
Cook on low for 7-8 hours until the juices run clear when sliced, or until chicken reaches 165° on a meat thermometer inserted in the thickest part of the thigh.
Notes: