In a bowl, combine flour, sugar, butter, salt, water, and egg.

Knead until a smooth, soft dough forms (by hand or mixer).

Wrap and chill in the fridge for 30 minutes.

In a saucepan, cook cherries with butter, vanilla sugar, and sugar.

Add lemon juice and zest.

Once the mixture starts to bubble, pour in water mixed with starch.

Cook until thickened to a jam-like consistency.

Roll out the chilled dough into a circle.

Line a 28 cm cake tin with the dough and press edges up the sides.

Pour the cherry filling into the center.

Bake at 180°C (350°F) for 40 minutes.

Beat egg whites until soft peaks form.

Gradually add powdered sugar and beat until stiff and glossy.

Spread the meringue over the baked tart.

Return to oven and bake for another 10 minutes until lightly golden.