Preheat the oven to 220°C/425°F. Grease a 20 x 30cm tin.
Fold out the pastry to cover the base and sides of the tin. Gently press into the tin, prick all over with a fork and place in the freezer for five minutes.
Top with baking beans and bake blind for 5 minutes. Remove from the oven, cool for 5 minutes and reduce the oven temperature to 180°C/350°F.
To make the frangipane, place the butter, extract, sugar and egg yolks in a bowl, beat until light and fluffy, then stir in the flour and ground almonds. Spread over the pastry base, sprinkle on the berries and bake for about 25-30 minutes, or until golden brown
Tip: We used blackberries, blueberries, raspberries and redcurrants, but you could use any combination of frozen berries.