Pass the popcorn infused milk into a jug, through a sieve, squeezing as much liquid out of the popcorn as possible.
Whilst the milk is straining, add the toasted milk powder, glucose syrup & half the brown sugar into a saucepan.
Next, place the saucepan onto a set of scales then pour in the infused milk. Top up with enough whole milk, to bring the weight up to 420 grams. Whisk the milk to combine then set aside.
Add the remaining brown sugar & the egg yolks into a mixing bowl & whisk together.
Place the pan of milk over a low heat & cook until steaming hot.
When the milk is steaming (don't let it boil!), pour a third into the yolks, whisking as you do so.This is called tempering the yolks. Pour the now tempered yolks back into the saucepan of milk then cook the custard over a low heat until it reaches 82°c/180°f, making sure to stir constantly with a rubber spatula.
Once cooked, take the custard off the heat & stir in the double cream. Pass the custard into a bowl, through a sieve then leave to cool, stirring occasionally.
Once cool, place a piece of baking paper onto the custard’s surface & refrigerate overnight.