Cut the steak into 2 cm cubes.
Peel and roughly chop the onions.
Chop the speck into large lardons.
Sauté the steak with the onions and speck in butter in a flameproof casserole dish for 5 minutes.
Add the sugar and let it caramelise.
Cover with the beer and season with salt and pepper.
Cut the pain d’épices into cubes, mix them with the mustard,