In a small saucepan off the heat, combine the sugar and cornstarch. Whisk in the eggs and egg yolk, then add the lemon juice and water. Bring to a boil over medium heat, stirring constantly and scraping the bottom and sides of the pan, until the curd has thickened. Remove from the heat and strain through a sieve. Cover with plastic wrap directly on the surface of the curd and refrigerate for 1 hour or until completely chilled.
Trifle
Using a 2-tbsp (30 ml) ice cream scoop, shape 4 scoops of vanilla ice cream, 3 of raspberry sorbet and 3 of mango sorbet. Place on a parchment-lined plate in the freezer while preparing the trifle.
Arrange one-third of the cake cubes over the bottom of the pan. Still using the ice cream scoop, arrange a layer of ice cream and sorbet over the cake cubes, alternating the flavours. Drizzle with one-third of the lemon curd. Repeat the sequence twice, using the reserved scoops of ice cream and sorbet to top the trifle. Garnish with the remaining curd. Freeze for 4 hours or until firm.
When ready to serve, unmould the trifle, cut into wedges and top with the raspberries and raspberry coulis.
Note from Ricardo
To obtain 1 cup (250 ml) of raspberry coulis, purée 2 cups (280 g) of raspberries with 1/4 cup (55 g) of sugar in
a blender. Strain through a sieve, if desired.