1Add 175 grams of melted butter, half a cup of icing sugar, 200 grams of plain flour, and a teaspoon of vanilla into a bowl for the base.
2Mix the ingredients until a dough forms.
3Press the dough into the bottom of a lined baking tray.
4Bake in the oven for about 18-20 minutes at 170°C.
5While the base bakes, prepare the blueberry swirl by adding 1.5 cups of blueberries, 3 tablespoons of white sugar, and 1 tablespoon of lemon juice into a saucepan.
6Heat the blueberry mixture over medium heat until the berries release their juices and the mixture thickens slightly.
7Add a teaspoon of cornflour to the blueberry mixture and keep it over the heat for another 1-2 minutes until it thickens.
8Take the blueberry mixture off the heat and set it aside to cool.
9Remove the base from the oven once it has a golden color and let it cool completely.
10For the white chocolate lemon ganache filling, add 200 grams of white chocolate into a bowl.
11Pour half a cup of very hot cream over the white chocolate.
12Let it sit for a minute to melt the chocolate, then stir until smooth.
13Add the zest of two lemons and 1 to 2 tablespoons of lemon juice to the ganache mixture, depending on desired lemon flavor.
14Stir all the ingredients for the ganache together.
15Pour the white chocolate lemon ganache filling over the cooled base.
16Add dollops of the blueberry compote over the ganache.
17Swirl the blueberry compote into the ganache with a knife to create a marbled effect.
18Put the tray into the fridge for at least 6 hours, or preferably overnight, to set.
19Once set, cut the lemonberry dream slice into individual pieces.