Croque poulet cancoillotte
chicken breasts • multigrain sandwich bread • white mushrooms (about 300 grams) • cancoillotte cheese, plain or garlic (about 8.8 oz / 250 grams) • butter plus 1 extra pat (about 1.5 oz / 40 grams) • all-purpose flour (about 1.5 oz / 40 grams) • milk (about 1/2 liter) • garlic cloves (if using plain cancoillotte) • Olive oil • Salt • Black pepper • Ground nutmeg