Combine sherry, garlic, oil, thyme, salt, and pepper in a shallow pan to create the marinade.

Add chicken to the marinade, cover, and refrigerate for at least 30 minutes.

Melt butter in a frying pan over medium-high heat.

Quickly brown the chicken breasts on both sides.

Reduce heat to medium-low, cover the pan, and cook for 15-20 minutes, or until chicken is cooked through.

Transfer chicken to serving plates.

Add water to the pan to deglaze, scraping up any browned bits.

Add the remaining marinade to the pan.

Bring the sauce to a boil and simmer until reduced by half, about 5 minutes.

Stir in heavy cream or a low-fat milk and water alternative and heat through.

Pour sauce over chicken breasts.

Serve with noodles or rice and roasted seasonal vegetables.