Heat the oven to 170c, 150cFan, 325F, gas 3.
Cut the hot cross buns in half and butter the cut sides, sprinkle with half of the chocolate chips, sandwich together again and place in a baking dish.
Beat the egg, milk and sugar together and pour over. Scatter with the remaining chocolate chips and bake for 30-35 minutes until just set.
I have cooked this
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