Prick pie shell and bake at 450 F 5 minutes. Set aside. Reduce oven temperature to 350 F. Mix the brown sugar with flour until blended. Spoon over bottom of partially baked pie shell. Combine the cream, extract, and nutmeg; pour over sugar in pie shell. Dot with the butter. Bake at 350 F about 55 minutes, or until crust is lightly browned and filling is set.