Step 1

Preheat the oven to 150ºC, gas mark 2. Pour the milk into a small pan. Cut the orange zest into long strips, add to the milk (reserve some for decoration), and warm over a low heat until it’s about to start simmering, then remove and set aside to infuse for at least 15 minutes.

Step 2

Have a 20cm round cake tin or flan tin ready. It needs a solid base, not loose-based or springform. Tip the sugar into a small heavy-based pan or frying pan. Add 3 tbsp orange juice and stir over a low heat until the sugar melts. Increase the heat, then boil for 3-4 minutes, swirling the pan so the sugar colours evenly for a dark golden caramel. Act quickly to prevent the caramel from burning, by pouring it into the flan or cake tin, tilting to cover the base. Sit the tin into a deep roasting tin.

Step 3

In a large jug, beat together the condensed milk and eggs. Through a sieve, pour in the orange-infused milk. Stir well to combine, then sieve the mixture into the flan tin over the set caramel. Pour boiling water into the roasting tin until the water comes ¾ of the way up the flan tin. Cook in the oven for 50 minutes to 1 hour, until the flan is set, but still wobbles a bit when given a gentle shake (the pudding centre should read 75ºC with a digital thermometer).

Step 4

Remove from the oven, lift the flan from the water bath and set aside to cool. Cover and chill in the fridge for at least 3 hours, or preferably overnight.

Step 5

To unmould the flan, run a sharp knife along the edge. Place a large, upturned, lipped plate over the top and flip it over, taking care to catch all the caramel sauce. Cut the skin and pith from the second orange and slice into rounds. Serve, topped with the orange slices and reserved zest.