Rhubarb and Custard Tartlets

Make Custard

1. Start by making custard. Carefully cut vanilla bean in half, scrape out seeds and place in saucepan with milk, empty vanilla pod and half the superfine sugar. Put pan on low heat and warm through until vanilla infuses and sugar melts, being careful not to scald milk.
2. In separate bowl, whisk egg yolks with rest of superfine sugar until they go pale and fluffy, then add cornstarch and mix through.
3. Remove vanilla pod from milk, then pour hot milk little by little on to egg yolks, whisking constantly. This tempers yolks, which gets them used to heat ahead of cooking. When you have mixed in all milk, pour mixture back into pan and place on low heat. You need to slowly warm up custard while constantly whisking and scraping bottom of pan until it thickens enough to coat back of spoon. I use a silicone spatula and make sure that no part of it stays on the bottom of the pan for too long, otherwise the egg can overcook and go lumpy. Custard should be wonderfully thick and wobbly, but do not overcook it and do not rush. The minute it thickens, take off heat and immediately push it through sieve into bowl to cool.
4. If not using custard straight away, scatter small amount of confectioner’s sugar over surface to act as buffer, then press sheet of parchment paper or plastic wrap on to surface so that it doesn’t form skin in fridge. You can make this in advance.

Assemble and Bake Tartlets

1. Preheat oven to 425°F. Roll puff pastry out on baking sheet lined with parchment paper. You can either make one big tart or individual ones, so cut sheet of puff as you wish — I usually cut it into six sections. Carefully score edges of pastry, leaving a ¾” border around edge. Be careful not to go right through pastry, but make sure your incisions are deep enough and connect with each other; this lets edges of pastry rise.
2. Take few spoons of custard and spread generously over inner square of pastry, being careful not to go over scored borders. I like to add about a finger’s depth of custard. Cut rhubarb into lengths and place on top of custard, nestling them in a little. You want to cram on as much rhubarb as possible. You can make tarts up to this stage, then chill in fridge for up to 24 hours until ready to bake.
3. Warm apricot jam in pan with tiny splash of water until you have paintable mixture, then with pastry brush, paint rhubarb and edges of pastry. This will ensure pastry has a lovely sheen and helps it go golden brown. Bake for about 20 minutes, or until pastry has picked up some nice color and rhubarb is cooked. Remove from oven and sprinkle with a little turbinado sugar. Leave to cool for a few minutes, but definitely serve while still warm.