Fry the chicken breast in the hot oil and season with salt and pepper. Stir in the curry powder and fry briefly, then add the port wine and stew covered over a mild heat for 5 - 8 minutes, turning once in between.
Halve and core the grapes, pluck the salad into bite-sized pieces.
Remove the meat from the pan and cut into thin strips. Mix the gravy with the crème fraîche and reduce to a creamy sauce. Season with salt, pepper, lemon zest and juice.
Spread the lettuce leaves, grapes and meat on plates and cover with the sauce. Scatter chives on top.