Caramelised Banana Custard Doughnuts

I was making Rhubarb Doughnuts last week and, as much as I would have loved to have an abundance of rhubarb doughnuts, I only had enough to fill half of the doughnut dough. I had seen a croissant shaped doughnuts on Instagram and really wanted to try it out. I also had a craving for banoffee pie so I decided to mash the two ideas together.

I love banana desserts but often overlook it as a flavour. These combine dark caramelised bananas with a rich, smooth mascarpone custard. The croissant shape isn’t too difficult, especially if you’ve shaped croissants before. They prove up a treat and I think they look beautiful with their cinnamon sugar coats.

Ingredients - makes 10 doughnuts
Brioche dough: dough recipe originally from The Boy Who Bakes (minus the lemon)
180g plain flour
180g strong white flour
20g caster sugar
1 tsp salt
7g fast action dried yeast
85ml whole milk
3 eggs
zest of 1 lemon
150g unsalted butter, room temperature
vegetable oil, for frying

Mascarpone Custard:
180ml double cream
180ml whole milk
1 tsp vanilla paste
pinch of salt
4 medium egg yolks
2 tsp cornflour
10g caster sugar
40g honey
250g mascarpone

Caramelised Banana:
70g caster sugar
1 large banana, peeled and cut in half
1/2 tsp vanilla paste
20g unsalted butter

Cinnamon sugar:
150g caster sugar
2 tsp ground cinnamon

Method
The day before
For the doughnut dough:
Place the flours, sugar, salt, yeast, milk, eggs and lemon into the bowl of a stand mixer fitted with a dough hook. Mix on medium speed for 5-10 minutes until you have a smooth dough. With the mixer on medium speed, gradually add in the butter in small pieces making sure the butter is incorporated before adding in more. Once all the butter has been added, increase the speed to medium-high and knead for 10 minutes until elastic and smooth. Leave to prove at room temperature for 30 minutes-1 hour or until doubled in size. Knock back the brioche and place into an oiled container, cover and leave to rest in the fridge overnight.

For the custard:
Place the double cream, milk, vanilla paste and honey into a saucepan over low heat. Mix the cornflour and sugar together before pouring over the egg yolks. Whisk the egg yolks together with the dry ingredients until well combined. Don’t let the sugar sit on the eggs or it will ‘burn’ them, causing them to form a skin and go clumpy.

Once the milk is just about simmering, pour a third of it over the yolks while whisking. Pour this back into the rest of the hot milk and whisk together. Place the custard over low heat, stirring continuously until it starts to bubble. Once it starts bubbling, whisk it for approx. 30 seconds-1 minute until it coats the back of a spoon and the cornflour has cooked out. Pour into a container, place clingfilm on the surface and refrigerate until completely cold.

For the caramelised banana:
Place the caster sugar into a frying pan over low heat. Leave the sugar to melt, nudging it around occasionally to stop it from burning but not stirring, until you have a light golden caramel. Take the pan off of the heat and add in the banana halves. Coat the banana in the caramel before adding in the butter and vanilla. Place the pan back onto low heat and break up the banana into chunks with a wooden spoon. Cook until the butter has melted into the sugar to create a bubbling caramel. Take the pan off of the heat and mash the banana. Scoop the caramelised banana into a container and cover with clingfilm. Leave to chill in the fridge overnight.

The next day:
Cut out 10 large square pieces of parchment. Take the doughnut dough out of the fridge. Punch the dough down and tip it out onto a lightly floured surface. Divide the dough in half and place one half back into the fridge. Roll the dough into a 15x9inch rectangle. Mark one of the 15inch sides at every 3inches. On the opposite side, mark 1.5inches and then every 3inches. Cut from the first 3inch indent to the one that is 1.5inches on the opposite side, so you have a diagonal cut. Continue cutting to connect the indents with the opposite so you have five triangles. To shape the dough, lightly stretch the pointed tail of the triangle before rolling it up from the base of the triangle to the tip. Place each croissant shaped doughnut onto a piece of parchment with the tail of the croissant underneath. Repeat with the second half of the dough.

Loosely cover the doughnuts with clingfilm and leave to rise in a warm place for 1 hour, or until doubled in size.

When your doughnuts are nearly ready to fry, fill a large saucepan halfway full with oil and place over medium heat. It should be at least a couple of inches deep. Prepare a baking tray lined with kitchen towel for the doughnuts once they’re fried. Once your oil reaches 175°C, pick the proved doughnuts up by the corners of the paper and carefully lower them into the oil. Please be careful here as the oil is very hot. Fry as many doughnuts as fits comfortably in your pan, I usually go for 3 or 4. Remove the baking paper after 30 seconds with some tongs. Fry for 2-3 minutes on each side until golden brown. Lift the doughnuts out of the oil with a slotted spoon and leave to drain on the kitchen towel. Continue until all of the doughnuts are fried, making sure the temperature stays at 175°C.

Once your doughnuts have cooled enough to handle, fill a shallow bowl with the caster sugar and cinnamon for the cinnamon sugar. Roll the doughnuts in the sugar, covering them completely. Set aside until needed.

To finish the custard, beat the mascarpone in the bowl of a stand mixer to loosen. Add in a third of the custard. Whisk together before adding in the rest of the custard and whisking until you have a luscious soft cream. Add in the mashed caramelised banana and fold it through, leaving ripples of the banana throughout. Place the cream into a piping bag fitted with a plain nozzle.

When you’re ready to fill the doughnuts, take a sharp pairing knife and make a hole in the side of each doughnut. Give the knife a little wiggle inside the doughnut to make a little pocket for the filling. Fill the doughnut with the banana custard. Doughnuts aren’t a baked good that you can make in advance. They must be eaten on the day they’re made. Enjoy!