Add chicken to slow cooker and season with salt, pepper, minced onion and poultry seasoning.
Pour cream of chicken soup over the chicken, then add in cubed potatoes.
Cover and cook on low 6 hours.
Remove chicken and shred.
Add shredded chicken back in slow cooker and stir in frozen mixed vegetables and heavy cream; cover and cook an additional 20-30 minutes on low.
Meanwhile, bake biscuits according to package directions.
Split biscuits on plate and serve chicken pot pie on top of biscuits.