Half chicken breasts through to make 8 cutlets; pound very thin, about 1/4". Season on both sides with salt & pepper. Spread thin layer of mustard on 1 side, sprinkle with thyme. Arrange 1 slice cheese & 1 ham on 4 cutlets, leaving a little chicken exposed all around. Place remaining cutlet, mustard side down, over top, press down at edges to form 4 cutlets. Dredge in flour.

Beat eggs & lemon juice together .

Heat skillet with oil over med heat. Melt 1 Tbsp. butter into oil.

Turn 2 stuffed cutlets in egg batter and add to pan. Cook about 8 min., turning occasionally or until cooked through& golden. Transfer to platter & cover loosely with foil. Melt another Tbsp. butter in pan & cook remaining 2 cutlets.