In a saucepan, add the first grouping of ingredients (milk, butter, sugar, and vanilla). Place over low-medium heat. In a bowl, mix together the second grouping of ingredients, starting with the egg yolks, then whisking in the sugar. Mix in the flour and cornstarch, then whisk in the milk.

When the milk on the heat starts to simmer, remove from the heat and slowly pour into the egg mixture while whisking. Return everything to the saucepan, and whisk until the mixture thickens and boils. Once it comes to a boil, whisk for 30 seconds. This ensures that it sets.

Pour into a clean bowl with plastic wrap in contact with the surface. Cool completely. The pastry cream will look 'jellified' after cooling. Whisk well either by hand or in a mixer to smooth the cream before using.

Whip up the ½ cup (120ml) of heavy cream and mix into the cooled pastry cream. Chill until ready to use.

Preheat your oven to 375F/190C. In a saucepan, add the water, milk, butter, sugar, and salt. Heat until it comes to a full boil and butter is melted.

Take off the heat, and add all the flour at once. Stir strongly until a dough forms. Put back on the heat and stir continuously for 30 seconds until the dough pulls away from the sides and a film forms on the bottom.

Transfer dough from the saucepan to a clean bowl or a mixer with a paddle attachment. Mix several minutes on low speed until the dough is no longer steaming.

Add the eggs one at a time, fully incorporating each before adding the next. Check dough at 3 eggs lifting the spoon to see how the batter falls. It should be thick, silky smooth and fall in a point.

Pipe walnut sized mounds on parchment or a Silpat. You’ll need around 30 for the croquembouche. Pat any tips down with a wet finger.

Bake at 375F/190C for 25 to 30 minutes, not opening the oven until you see they are nicely golden brown. Test for done-ness by picking one up. It should feel light and hollow. Cool then fill with the cooled pastry cream.

Start by adding the water to a small to medium saucepan, then the sugar. Put on medium heat and just let sit until it starts to change color (no stirring!!). Once it starts to change color, you can swirl the pan if you need to redistribute the heat.

Take off the heat once it reaches the desired color, a light caramel. Dip the tops of the filled cream puffs in the caramel. Set aside to firm up. Reheat the caramel on low heat as needed to return it to a liquid state.

On a plate, cake board, or other serving surface, plot out the beginning circle. In diameter, it will be about 7 inches (18 cm) measuring from the outside of the choux.

Dip the side of each choux and stick to the base to form the first circle. For the following rows, you’ll need to dip the side and a little more to either the left or right to stick the choux to the choux below, and the one next to it.

Keep working your way up. At the top, angle two choux, but see what works! Sometimes it’s only one! Sometimes, it’s a trifecta of three! Only lasts one day! To serve, cut into with a serrated knife.