This tempting creation from Joni in Walkley features in the Sheffield Cookbook: Second Helpings.
You will need a piping bag fitted with a large star nozzle (around 1.5cm) with as many small teeth as possible to prevent the choux from cracking in the oven, giving it room to expand. You’ll also need a tube nozzle for filling the eclairs.
FOR THE FILLING
300g double cream
600g white chocolate
For the Choux
100g bread flour, sifted
3 medium eggs, at room temperature, lightly beaten
Icing sugar, for dusting
For the icing
Freeze-dried blueberry powder
For the filling, bring the cream to a gentle simmer in a medium saucepan. In another pan bring the blueberries,sugar and water to the boil until softened. Add the white chocolate to the cream and whisk untilsmooth. Once smooth add the blueberries and place in the fridge to set for 1 hour.
For the choux, preheat oven to 180°c. Bring the water, milk, butter, sugar and salt to a strong simmer in a medium saucepan over a medium heat.
Remove the pan from the heat and add all the flour at once. Stir vigorously until the flour is completely incorporated. (Tip: when adding the flour, sift it onto baking parchment and use this to shoot it into the pan all at once.)
Return to a medium heat and stir the dough. Cook until the dough reaches 75°c , around 2 minutes, or until a film forms on the bottom of the saucepan. Transfer the dough to a bowl and, using a stand mixer fitted with the paddle attachment, mix the dough on the lowest speed until it cools to around 60°c. This will take around 2 minutes. This can also be done with a hand mixer or spoon. Add one- third of the beaten eggs and mix on the lowest speed until combined.
With the mixer still running, add the rest of the beaten eggs slowly. Once incorporated, mix for an additional minute or two until the dough is smooth.
Prepare a Silpat or parchment-lined baking sheet. Transfer the choux to a piping bag fitted with a large star nozzle. Pipe the éclairs in 13cm lengths, about 2.5cm wide. Space the éclairs about 5cm apart as they will rise in the oven. Dust with icing sugar. Bake in the preheated oven for 40 minutes, or until slightly darker than a golden brown. Remove from the oven and make a thin slit at the bottom of each éclair while still hot to let the steam escape. Let cool completely before filling and glazing.
To finish, transfer the filling into a piping bag fitted with a long tube nozzle. Fill each éclair through the thin slit in the base. Mix together some icing sugar, a little water and freeze-dried blueberry powder until smooth. You want to reach a thick consistency that won’t drip.
Dip each éclair into the icing upside-down to cover the tops, the decorate.
The Sheffield Cookbook can be bought from Amazon, Waterstones and venues featured in the book.