• About 20 Oreo® cookies
• 175 g (6 oz) unsalted butter
• 400 g (14 oz) crunchy peanut butter
• 175 g (6 oz) icing (confectioners’) sugar
• 200 g (7 oz) very good quality dark chocolate

FINELY GRIND THE COOKIES IN A FOOD PROCESSOR. Melt 75 g (2½ oz) of the butter and combine it with the cookie crumbs.

PLACE THIS MIXTURE IN THE BASE OF A ROUND 24 CM (9½ INCH) TART (FLAN) TIN (PREFERABLY LOOSE-BASED), THEN LET IT SET IN THE FRIDGE FOR ABOUT 30 MINUTES.

ONCE IT HAS SET, BEAT THE PEANUT BUTTER WITH THE SUGAR IN A MIXING BOWL. Spread this mixture over the tart base.

MELT THE REST OF THE BUTTER AND THE CHOCOLATE VERY GENTLY IN THE MICROWAVE (IN 30-SECOND BURSTS, STIRRING BETWEEN EACH ONE) OR IN A DOUBLE BOILER (IN A MIXING BOWL PLACED OVER A SAUCEPAN OF GENTLY SIMMERING WATER). Stir well until the chocolate is smooth.

POUR THE CHOCOLATE OVER THE PEANUT BUTTER. Let the tart set for 1 hour in a cool place, avoiding the fridge so the chocolate keeps its glossy appearance.