Line a 20cm (8inch) square baking pan with baking paper and set aside.
Dough: In a medium bowl, mix together the flour, sugar, baking powder, vanilla and salt.
Add the butter and rub it in using your fingertips or a pastry cutter to form a crumbly dough.
Add the 3 egg yolks and gently mix until a dough forms. Try not to overwork the dough or it will become chewy.
Cut off one-third, flatten it down to 2 cm (1.5 in) thick, wrap it in cling film and place it in the freezer.
Take the remaining two-thirds of the dough and press it down into the prepared baking dish or tin.
Filling: In a medium bowl whisk the egg whites with an electric mixer on high speed until very stiff.
Gradually add the sugar, 1 teaspoon at a time. Whisk well between each addition until all the sugar has been added and you have a very stiff and glossy meringue mix.
Add the ground almonds to the meringue, ensuring they are incorporated and then spread evenly over the top of the dough in the tin.
Preheat the oven to 170°C fan / 375°F / Gas 5.
Strawberries: Clean the strawberries and cut them in half. In a medium bowl add the cornflour to the strawberries, ensuring there are no lumps of cornflour left.
Evenly distribute the strawberries over the almond meringue filling in the tin.
Remove the dough from the freezer and coarsely grate the dough over the top of the strawberries.
Baking: Place the tin in the middle of the oven and bake for 35-40 minutes, until lightly golden on top. Remove and let cool.
Cutting: Make sure to let the bars cool completely before cutting into 12 pieces and dust with icing sugar.(If you slice them while they are still warm, they won’t hold their shape.) As if these bars could get any more delicious, try topping them with vanilla ice cream or whipped cream.