Season the chicken with salt and pepper. Add oil to large skillet. Brown the chicken pieces in batches and remove from pan and set aside. Add the onions, and mushrooms. Let cook until onions are softened.
Add the garlic and cook 2 minutes. Remove with slotted spoon and set aside. Add the butter to the pan. when butter is melted add the flour and make a roux.
Slowly add in the chicken stock, chicken bouillon, and heavy cream whisking until smooth. Add the lemon juice. Taste and season with salt and pepper. Add the chicken back and let cook 3 minutes. Add the mushroom onion mixture and cook 2 minutes.
Serve over mashed potatoes, rice or pasta. Garnish with parsley