In a large cast iron skillet add 1 Tbsp butter and melt over medium heat.
Season the chicken with the salt, pepper and Italian seasoning. Add chicken to hot pan.
Cook on each side 5-6 minutes
Add the chicken to the slow cooker
Cover with lemon juice, lemon zest, garlic and the rest of the butter, cut into pieces
Cook on low 4 hours or high 2 hours
In a bowl, mix the half and half, cornstarch and chicken bouillon and whisk well.
Add the liquid mix to the slow cooker and cook an additional hour on high.