Stir the melted butter and sugar together in a bowl. Sieve the flour into the butter mixture and mix well. Stir in the egg. Make a ball and wrap the pastry in cling film. Chill for 30 minutes in the refrigerator.
Roll the pastry and press into 6 small tart tins, or one large tart tin. Cover with baking parchment.
Bake in the preheated oven until barely golden, about 20 minutes. Let cool.
Melt the redcurrant jelly in a microwave-safe bowl until liquid, about 10 seconds. Brush the jelly evenly over the bottom of the cooled pastry case.
Arrange the strawberries in a pretty pattern in the pastry case. Cover with whipped cream just before serving.