Preheat your oven to 350°F (175°C). Grease and flour the tart pans.

In a large mixing bowl, combine flour and sugar. Cut in chilled butter until the mixture resembles coarse crumbs. Gradually add cold water, mixing until the dough holds together. Roll out the dough and cut into circles to fit the tart pans. Press into the pans and chill for 15 minutes.

Once chilled, prick the base of each shell with a fork. Bake in the preheated oven for 10-12 minutes or until lightly golden. Remove from oven and allow to cool.

In a medium saucepan, combine sugar, cornstarch, and water. Cook over medium heat until thickened and bubbling. Remove from heat and stir in lemon juice and zest. Gradually whisk in egg yolks, then return to the heat for a further minute, stirring constantly. Remove from heat and add butter, stirring until melted.

Pour the lemon filling into the prepared tart shells, filling them to just below the rim. Allow to cool slightly while you prepare the meringue.

Using an electric mixer, beat egg whites and cream of tartar until soft peaks form. Gradually add sugar, beating until stiff, glossy peaks form.

Spoon or pipe meringue onto each tart, ensuring it covers the filling completely and seals to the crust. Use the back of a spoon to create decorative peaks.

Place the tarts back in the oven and bake for an additional 10-12 minutes, or until the meringue is lightly browned. Remove from oven and allow to cool before serving.

Serve the mini lemon meringue tarts at room temperature or slightly chilled. They are perfect on their own or paired with a scoop of vanilla ice cream.

Store any leftover tarts in an airtight container in the refrigerator. They will keep for up to 3 days, though they are best enjoyed fresh.