Preheat oven to 350 degrees Fahrenhiet. Slice 3/4 of the way horizontally through Chicken breasts, cutting through the rounded edge; open out, cover with plastic wrap and beat with a rolling pin to flatten. Cover each filet with a slice of Ham, then a slice of Gruyere. Set aside one tablespoon chives; sprinkle rest over Cheese. Roll up Chicken; secure with a wooden toothpick or string. In an ovenproof pan, heat oil; cook Chicken rolls gently, turning occasionally, until sealed. Pour off excess oil. Add garlic, wine and seasoning to pan, cover and cook in the oven for 25–30 minutes, until tender. Place roulades on a dish, remove toothpick or string and keep warm. Put pan and remaining contents on high heat and boil rapidly to reduce slightly; add Devon cream and remaining chives and heat th