Crush the digestive biscuit and stir with unsalted cream in a bowl. Pour into dessert mould and store it inside the fridge for 30 minutes.
Mix the lemon peel and 60g of granulated sugar to induce the aroma of lemon.
Mix all the ingredients of lemon curd and the processed granulated sugar and steam the mixture while stirring until the mixture starts to solidify.
Pour the mixture into the dessert mould in step 1.
Pour in the remaining egg whites into granulated sugar and stir it using egg beater. Place it on top of the tart and decorate it as you like.
Use a torch and roast the surface of the tart or put the tarts inside an oven to heat for 10 minutes under 200-230 degrees celsius and the tarts will be ready to serve.