Roll the pastry out thinly on a lightly floured surface, then stamp out 24 × 6 cm (2½ inch) circles with a fluted biscuit cutter and press into the buttered sections of 2 × 12-section mini muffin tins. Reknead and reroll the pastry trimmings as needed. Prick the base of each tart 2–3 times with a fork, then chill for 15 minutes.
Beat the eggs and sugar together, then mix in the melted butter, lemon rind and juice. Spoon into the tart cases and bake in a preheated oven, 180°C (350°F), Gas Mark 4, for 15 minutes until just set. The tarts will be quite puffed up when you first take them out of the oven, but as they cool they will sink down again.
Leave to cool in the tins, then loosen the pastry with a knife, lift the tarts out of the tins and arrange on a serving plate. Top each with a small spoonful of crème fraîche and grated lemon rind to garnish.