Wash the thyme, dab dry and remove the leaves. Peel onion and cut into rings. Wash the meat, dab dry and cut in half lengthwise. Tap the meat slices between 2 layers of foil flatter. Season with salt and pepper. Place 1 slice of ham on each and sprinkle with thyme. Roll into roulades and pin with 1 wooden skewer each
Heat the oil in a non-stick frying pan and fry the rolls for about 4 minutes, turning them over. Add the onion and fry briefly. Pour in broth and braise in the closed pan for 6-8 minutes. Remove the rolls and keep warm. Let the onion stock boil down a little. Season to taste with salt and pepper and serve