Place the chicken breasts in an even layer on the bottom of the crockpot.
In a medium bowl, whisk together the cream of chicken soup, chicken broth, frozen mixed vegetables, onion powder, garlic powder, dried thyme, salt, pepper, and optional paprika until well combined.
Pour the soup and vegetable mixture evenly over the chicken in the crockpot, making sure the chicken is well coated.
Cover and cook on LOW for 6–8 hours or on HIGH for 3–4 hours, until the chicken is cooked through and very tender.
About 30 minutes before serving, use two forks to shred the chicken directly in the crockpot, stirring to combine it with the sauce and vegetables. If you like it creamier, stir in the optional milk or half-and-half at this point.
Open the can of refrigerated biscuit dough and cut each biscuit into quarters (or smaller pieces for bite-size dumplings).
Gently drop the biscuit pieces into the crockpot, spreading them out over the surface. Lightly press them down so they’re coated in the sauce, but don’t over-stir.
Cover and cook on HIGH for an additional 25–35 minutes, or until the biscuits are puffed, cooked through, and no longer doughy in the center.
Taste and adjust seasoning with additional salt and pepper if needed. Serve warm straight from the crockpot.
