Rhubarb goes so effortlessly well with walnuts.  This slice has a simple buttery shortcrust base, sticky and slightly tangy rhubarb filling and to top it off it is smothered with walnut whipped meringue. Delicious!

Preparation time - 1 hour 

Cooking time - 45 minutes

Skill - moderate

Serves - 12 slices

Ingredients

Shortcrust pastry 

180g softened butter

100g caster sugar

2 egg yolks

225g all purpose flour

¾ tsp baking powder

Rhubarb 

450g rhubarb

300g raw cane sugar (or caster sugar)

1 orange, zest and juice

Meringue

2 egg whites (room temperature)

120g raw cane caster sugar (or caster sugar)

1 tsp vanilla extract

Pinch salt

Pinch cream of tartar (optional)

100g walnuts, coarsely ground

Method

Begin by making the pastry.  Beat the softened butter with the sugar until pale and creamy.

Add the egg yolks and beat well to combine.

Sift the dry ingredients and mix to combine.  

Turn out onto your workbench and bring the dough together. Wrap and chill in the fridge for at least 30 minutes.

To make the rhubarb filling.  Cut the rhubarb into 1 cm pieces and add to a medium saucepan along with the sugar, orange zest and juice.

Cook over a low heat so the sugar can dissolve.  Once the sugar has dissolved, turn the heat up and cook a little more vigorously so that the rhubarb softens and the juice thickens and becomes more jam-like.  Remove from the heat and cool.

Roll the pastry out to fit a 20x20cm baking tin. Line the tin with baking paper allowing the paper to go up the sides.

Place the pastry along the bottom of the tin and press to fit corners.  Prick the surface all over with a fork and chill for another 30 minutes.

Preheat the oven 170C fan bake / 180C

Cook the chilled pastry shell for 10-15 minutes or until lightly golden. Remove from the oven and allow to cool a little before spreading over the rhubarb mixture.

To make the meringue - place the egg whites into a clean bowl of your mixer, add a pinch of salt and whisk on medium until doubled in size.

Gradually add in the sugar, beating all the time until you have stiff whites.

Add the vanilla and cream of tartar (if using) this helps with the stability of the egg whites.

Fold in the walnuts and spread lightly over the rhubarb.

Bake for 10-15 minutes or until the meringue has lightly coloured and feels crisp on the outside.

Cool before cutting.