Monte Cristo sandwiches with potato crisps

1.For potato crisps, thinly slice potato on a mandolin, place in a bowl of water and set aside for 5 minutes. Meanwhile, heat oil in a deep saucepan or deep-fryer to 180C. Dry potato well on absorbent paper and deep-fry in batches, stirring occasionally, until golden (1-2 minutes; be careful as hot oil will spit). Drain well on absorbent paper. Season generously with sea salt flakes and set aside.

2.Preheat oven to 180C. Spread bread with mustard, top half the slices with ham and cheese, sandwich with remaining bread. Dip sandwiches in eggwash and turn to coat all edges. Heat half the butter in a large frying pan over medium-high heat and cook half the sandwiches, turning once, until golden (1-2 minutes each side), then transfer to an oven tray lined with baking paper. Wipe pan clean and repeat with remaining sandwiches. Transfer tray to oven, cook until cheese melts (4-5 minutes) and serve hot with potato crisps.