Making the CrustLine the tart ring with the dough and freeze it for about 20 minutes to prevent the sides collapsing when the crust is baked. Preheat the oven to 325°F (160°C/Gas mark 3). Blind bake the crust for 15–20 minutes until golden. Allow to cool and then, using the zester, file down the edges of the pastry so the rim is perfectly smooth.
Making the Lemon Cream
Put the lemon juice, eggs, and sugar in a heatproof mixing bowl and stand the bowl over a pan of hot water. Whisk continuously until the mixture has thickened. Meanwhile, soak the gelatin sheets in a bowl of cold water. When the lemon mixture reaches 140°F (60°C), remove the bowl from the heat. Squeeze the water from the gelatin sheets and stir them in until dissolved. Stir in the softened butter and process with the stick blender until smooth.
Assembling the Tart
Pour the lemon cream into the tart crust, filling it to the rim. Smooth the top with a spatula (or palette knife) and leave to set. Brush the warmed clear neutral glaze over the top.
CHEFS’ NOTES
To ensure the base of the tart crust stays crisp, you can “waterproof” it with a little melted white chocolate or, better still, cacao butter. Simply brush the inside of the cooled crust with the chocolate or cacao butter and leave to set before pouring in the lemon cream.