(optional) Cook the chicken on a grill or under a very hot broiler in the oven for about 3 to 5 minutes on each side, depending on their thickness and the intensity of the heat. (The chicken can also be sauteed in a frying pan.) Set aside. In a large frying pan over moderately low heat, melt butter and saute shallot until translucent, but not browned. Add pesto, tarragon, vinegar, jam and wine, season with salt and pepper, and stir to combine well. Add the chicken and raspberries and cook on low heat for about 5 minutes, turning the chicken occasionally, to heat through and blend the flavors. Serve accompanied by pasta.