• Heat the oven to 200°C/180°C fan/Gas 6. Draw 10 12cm lines, equally spaced 6cm apart, on a sheet of baking paper. Flip the baking paper over so that the lines are on the underside and use it to line your 38 x 33cm baking sheet (or baking tray).

Make the choux pastry

• Sift the flour, sugar and salt together onto a separate sheet of baking paper.
• Put the 65ml of milk and 55g of butter, with 65ml of water into a medium saucepan and heat it gently until the butter melts. Don't let the water boil before the butter has melted.
• Once the butter has melted, bring the mixture to the boil, then tip in the flour mixture. Remove from the heat and beat furiously with a wooden spoon. The mixture will look scrambled at first, but keep beating until it comes together as a ball.
• Return the pan to a low heat and stir for 3-4 minutes, to dry the choux pastry out slightly. It's ready when it leaves the sides of the pan clean.
• Tip out the choux pastry onto a dinner plate and spread it out using the back of a wooden spoon. Leave it to cool until just warm.
• Scrape the just-warm choux pastry into a large bowl. Then beat 2 eggs in a small bowl and, a little at a time, add the eggs to the pastry, beating with an electric hand whisk, or a wooden spoon, between each addition until smooth.
• Fit a large piping bag with the large round nozzle. Spoon the mixture into the piping bag. Using the drawn lines as a guide, slowly pipe 10 thick and even 12cm-long lines (about 2-3cm in diameter) over the baking paper. Try to keep the lines straight and even.
• Bake the mixture for 30 minutes until risen, golden brown and crisp. Using a skewer or cocktail stick, pierce a hole in both ends of each eclair to allow the steam to escape. Return the eclairs to the oven for 5 minutes to dry out.
• Remove the eclairs from the oven and transfer them to a wire rack to cool completely (about 15 minutes) while you are making the rest of the recipe.

Make the meringue kisses

• Reduce the oven to 120°C/100°C fan/Gas 1 and re-line the baking sheet (or baking tray) with a new sheet of baking paper.
• In a clean, large bowl, whisk the egg white with an electric (or rotary) hand whisk on low speed until small bubbles form (about 2-3 minutes). Increase the speed to medium and beat until white and foamy.
• Increase the speed to high, and 1 teaspoon at a time, add the 60g of sugar, whisking well between each addition. Continue whisking until you have added all the sugar and the meringue is very stiff and glossy (about 5 minutes).
• Spoon the meringue into the small piping bag fitted with the small open star nozzle. Pipe about 60 small kisses onto the re-lined baking sheet (or tray). Squeeze lightly on the piping bag without touching the baking paper and then pull up quickly to create the tip of the kiss.

  (Tip: stick the edges of the baking paper down with a little dab of meringue).
• Place the baking sheet on the centre rack of the oven and bake for 45 minutes, until the meringues are dry and easily peel off the baking paper. Turn the oven off and leave the meringues inside with the door closed until needed.

Make the passion fruit crème pâtissière

• In a clean, large bowl, whisk the 3 egg yolks and 50g of sugar together by hand, then whisk in the 35g of flour to create a smooth paste.
• Pour the 125ml of milk and 125g of cream into a clean, medium saucepan, then warm the mixture over a low heat until it just starts to simmer (about 4-5 minutes).
• Slowly pour the warm milk mixture into the egg mixture, whisking continuously, until combined.
• Pour the mixture back into the pan and whisk continuously over a medium heat for about 4-5 minutes, until smooth and thick and the mixture no longer tastes floury.
• Remove the crème pâtissière from the heat and, using a spatula, pass the mixture through a sieve into a clean bowl. Add the 20g of butter and stir until melted and thoroughly combined.
• Stir through 100g of the passion fruit curd. Place a piece of cling film over the surface of the crème pâtissière to stop a skin forming and chill in the fridge until ready to use.

Make the caramel

• Tip the sugar into a small saucepan (but large enough to dip in the eclairs) and place it over a medium heat. Once the sugar starts to melt and colour at the edges, swirl the pan so that the sugar melts completely.
• Cook the caramel over a medium heat until it has turned an even amber colour. Remove the pan from the heat and leave the caramel to cool for 2 minutes.
• Using tongs, or your fingertips if you're experienced (but taking extra care), dip the top of an eclair into the caramel to coat the surface. Leave any excess caramel to drip off, then scrape any remaining drips from the eclair on the edge of the pan to give an even layer.

  Place, coated side upwards, on a wire rack to set. Repeat for the rest of the eclairs. Leave the caramel to set for 10 minutes before decorating.

  (Tip: the caramel is very hot, so watch your fingertips while dipping. If the caramel starts to harden, place it back over a low heat to re-melt.

Assemble and decorate

• Spoon the chilled crème pâtissière into the large piping bag fitted with the filling nozzle. Insert the nozzle into the steam hole (created earlier) at one end of a coated eclair and fill until you feel some resistance. Repeat at the other end, this time filling until some crème pâtissière escapes from the opposite hole.
• Spoon the remaining 20g of passion fruit curd into the small piping bag. Snip a tiny hole in the end of the bag and pipe dots on top of the caramel glaze where you would like the meringue kisses to go. Carefully peel the meringue kisses off the baking paper and place them on top of the dots of curd.

  (Tip: You will have more meringue kisses than you need. Enjoy them as a sweet treat, serve them with ice cream or use them to decorate cakes).
• Pipe dots of the remaining curd and the remaining crème pâtissière on top of the eclairs. Then, decorate with mint leaves, if using. Carefully place the eclairs on a serving plate or cake stand and serve immediately.