Season the chicken breasts with black pepper, kosher salt, and garlic powder. Over medium or medium-high heat, cook the chicken in extra virgin olive oil until done. Remove from the pan + keep warm.
In the same pan, cook the country ham until browned on both sides. Add a little extra oil to the pan if need be. Remove when done, allow to cool and dice into small pieces.
With 1/4 stick of butter in your pan, cook the celery and shallots for 3-5 minutes. Add minced garlic and cook for another minute. Add in the flour, evenly coating the celery + shallots, and cook for 30-45 seconds. Pour in chicken stock and allow to cook/reduce for 3 minutes.
Add in Hall's Beer Cheese + the heavy cream, mixing constantly until the cheese has thinned and all ingredients combine into a smooth sauce. If too thick, add chicken stock until you've reached your desired consistency. Stir in Worcestershire + dijon mustard. Fold in diced country ham. Add chicken breasts back to the pan, cover them in Hall's Beer Cheese Sauce, and allow to cook + combine for 1-2 minutes.