Ingredients
Method
Preheat oven to 180°C/160°C fan. Line an oven tray with baking paper. Grease a 20cm x 30cm slice pan. Line base and sides with baking paper, extending paper 5cm over the sides.
Rinse rhubarb, shaking off excess water. Place on lined oven tray, then sprinkle with sugar. Bake rhubarb for 20 minutes or until tender yet still holds its shape. Cool on tray.
Reduce oven to 170°C/150°C fan. Beat butter, extra sugar and vanilla with an electric mixer until pale and fluffy. Add egg yolks, one at a time, beating well after each addition. Fold in combined sifted flour and baking powder until combined. Press mixture evenly over base of lined slice pan.
Bake base for 15 minutes or until light golden and firm. Cool base for 15 minutes. Arrange cooled rhubarb on top in a single layer.
To make the topping, whisk egg whites with an electric mixer until soft peaks form. Gradually add sugar, whisking continuously for 5 minutes or until mixture is thick and glossy. Fold in vinegar and cornflour. Transfer two-thirds of the meringue to another bowl and fold in coconut. Spoon coconut meringue over rhubarb and smooth the surface. Place remaining plain meringue in spoonfuls over the coconut meringue, using the back of a spoon to create peaks and swirls.
Bake slice for 35 minutes or until meringue is light golden and a crust is formed. Cool completely in the pan before cutting into squares to serve.