Ice cream profiterole sandwiches with salted chocolate sauce

Method

1. For the choux pastry, put the butter and 150ml water in a saucepan set over a medium heat. When the butter has melted, turn up the heat and bring to a rolling boil.
2. Meanwhile, in a mixing bowl, combine the flour, sugar and salt then, in one go, pour into the boiling butter/water mixture. Beat vigorously with a wooden spoon until the mix clumps together to form a ball that fully comes away from the sides of the pan. Tip the dough into a large mixing bowl and use the spoon to spread the mixture up the sides (to help it cool more quickly). Leave to cool to room temperature.
3. Heat the oven to 220°C/200°C fan/gas 7. Add the 4 beaten eggs, little by little, to the cooled dough, adding more only once the previous addition is mixed in. The mix will look as if it’s about to split but it will come back together after beating. You might not need all the eggs or you might have to add an extra splash of milk to reach dropping consistency.
4. Put the choux mixture in the piping bag, then pipe 8 buns about 4cm wide and 4cm high onto each baking sheet, spacing at least 4cm apart. Use your finger to brush a little of the beaten egg over each one to smooth out any peaks. Bake for 25 minutes, then lift up the profiteroles and use a skewer to poke a small hole in the bottom of each one to let out the steam. Bake for 2-3 minutes more until golden and crisp. Cool on a wire rack.
5. Once cool, cut each choux bun in half horizontally, then sandwich together with a scoop of ice cream. Put the buns on a tray and keep in the freezer while you make the sauce.
6. For the sauce, melt both types of chocolate in a heatproof bowl set over a pan of barely simmering water (don’t let the bowl touch the water), then remove from the heat and set the bowl aside. Put the milk, cream and sugar in a small pan and heat gently until just steaming. Pour the hot milk mixture over the melted chocolate and mix briefly to combine, then pour back into the pan and add the 1 tsp salt. Keep warm. Serve the profiteroles with the hot chocolate sauce drizzled over, sprinkled with a little extra flaked sea salt, if you like.