Lemon curd sandwich biscuits

Name: Lemon curd sandwich biscuits
Prep time: 40 min
Cook time: 12 min
Total time: 52 min
Cuisine: British
Ingredients: 60g unsalted butter; 120g caster sugar; Finely grated zest and juice of 2 unwaxed lemons; 1 tsp cornflour; 2 large eggs, lightly beaten; 90g unsalted butter, at room temperature; 175g caster sugar, plus more to sprinkle; 1 large egg; 1 tsp vanilla bean paste; Finely grated zest of 1 unwaxed lemon; 200g plain flour, plus more to dust; About ½ jar of lemon curd or see homemade recipe above