Whisk everything together until you have a medium peak.

In a saucepan over a medium heat, heat the milk and vanilla until steaming.

Meanwhile, in a bowl whisk the yolks, sugar, cornflour and salt for 1 minute until thick.

Slowly pour the hot cream over the yolk mixture, whisking constantly. Pour the mixture back into the pan and cook on a medium heat. Keep whisking and then once it starts to bubble cook for a further minute.

Pass the mixture through a sieve and then whisk in the cold butter. Cover the surface directly with cling film and chill for 4 hours. Whisk it up until it is smooth.

Prepare the Creme Patissiere as above.

Once the Creme Patissiere has cooled, whisk together the ingredients for the the Creme Chantilly. Whisk it to a medium peak then fold it through the Creme Patisserie in two parts. Make sure you’ve whisked the chilled Creme Patissiere so it is smooth before you fold the chantilly in.

You can use it straight away but it will be slightly thinner. Or you can chill it for a few hours in the fridge and the consistency will be thicker. Or whisk the cream so that it is thicker and then fold that through the Creme Patisserie!