Make the crème pâtissière

• Combine the eggs, sugar, flour and vanilla paste in a bowl, whisking until smooth.
• Warm the milk in a saucepan until warm but not hot, then slowly stream it into the egg mixture while whisking constantly to temper the eggs.

Cook the custard

• Return the mixture to the stove and whisk constantly over medium-low heat until it thickens.
• Bring to a boil for 30 seconds to cook the flour through.

Cool the custard

• Transfer to a bowl and cover with plastic wrap pressed directly onto the surface to prevent a skin forming.
• Let it cool completely.

Make the donut dough

• Add all the dry ingredients to a bowl before adding the tepid water.
• Mix until the dough becomes a little stretchy, then add the butter and mix again.
• Cover and let the dough rest for an hour, then knock it back.

Fry the donuts

• Shape the dough into balls and fry in hot oil for a few minutes on each side until golden.
• Drain on a wire rack and let cool completely.

Make the crème diplomat

• Whip the cream to soft peaks.
• Fold the whipped cream into the custard in a 1.5:1 ratio of custard to cream.

Fill the donuts

• Create a hole in each cooled donut with a paring knife and push side to side to create a crevice inside.
• Add the crème diplomat to a piping bag with a 5 mm nozzle and fill the donuts completely.

Caramelize the tops

• Melt the sugar slowly on the stove to make a basic caramel.
• Dip the top side of each donut in the caramel, being extremely careful as the sugar is very hot.
• Place onto a wire rack to cool completely.