Sprinkle the chicken breasts with the salt and pepper and put them on a plate. Stir the honey into the raspberry vinegar and mix well. Dribble this mixture over the breasts and allow them to marinate for 15 minutes.
Preheat the oven to 100'C (2OO'F or Mark 1/4). In a heavy frying pan, melt the butter over medium-high heat, and saute the breasts until golden - about 4
minutes on each side. Transfer the chicken to a serving platter and put the platter in the oven to keep warm. Add the wine and shallot to the pan. Reduce the liquid until it barely coats the pan - there should be about 2 tablespoons. Reserve 12 of the raspberries for a garnish. Add the stock and the remaining raspberries and reduce by half. Puree the mixture in a food processor or blender, then strain it through a fine sieve.
Return the sauce to the pan and bring it to the boil. Spoon it over the chicken and garnish with the reserved raspberries and the mint sprigs, if desired.
