Step 1

Place butter and sugar in a stand mixer with the paddle attachment and beat until smooth. Beat in eggs until combined. Fold in flour, baking powder and a pinch of salt flakes. Divide dough in half and shape into rectangles. Enclose in plastic wrap, and chill for 2 hours.

Step 2

Remove pastry from fridge 10 minutes before rolling. Roll each piece of pastry between sheets of baking paper until 3mm thick. Use one sheet of pastry to line base and sides of an 11cm x 34cm loose-base fluted tart pan and chill for 30 minutes. Cut remaining pastry into 7mm wide strips. Lay the strips on a tray and place in the freezer for 30 minutes.

Step 3

Preheat oven to 180°C. Mix jam and cornflour together in a bowl and spread over the chilled pastry base. Brush edges with egg and arrange strips over the top. Brush pastry with egg and chill for 15 minutes.

Step 4

Place tart pan on a baking tray and bake for 1 hour or until pastry is golden. Remove from oven and cool to room temperature. Cut into slices and serve.