Credit to Nigel Slater, whose recipe this is; longsince a firm favourite when entertaining guests to dinner for speed, simplicity and downright tastiness.
several apples (eaters, not cookers)
Core and slice the apple into pretty thin slices as if making tarte tatin. Put slices in mixing bowl, pour over sufficient calvados to marinade the apples without wasting too much in a pool at the bottom. Allow apples to stand for as long as you have – mixing occasionally to keep the calvados going in.
Heat grill. Cut brioche into slices and gently toast both sides. place gently toasted brioche on grill pan and layer apple slices one layer deep (as with tatin) on top covering as much as the brioche as possible (exposed brioche will burn). Now shake over icing sugar in a generous though not engulfing quantity. Place under grill until the sugar has started to caremelise or the brioche threatens to burn. Serve with vanilla ice cream.