1 cup (250ml) freshly-squeezed lemon juice
Grated zest of two lemons, preferably unsprayed
3/4 cup (150g) sugar
12 tablespoons (170g) butter, cut into cubes
4 large eggs
4 large egg yolks
One pre-baked 23cm tart shell (any good shortcrust pastry will do but Maggie Beer’s sour cream pastry never fails)

Preheat the oven to 180ºC.
In a medium-sized non-reactive saucepan, heat the lemon juice, zest, sugar, butter, eggs and egg yolks. Have a mesh strainer nearby.
Stir until the butter is melted, then whisk the mixture continuously until it thickens and holds its shape. When you lift some of it up with the whisk it should visibly mound up when dropped back down over the rest of the mixture in the saucepan. It should only take a few minutes.
Pour the warm lemon curd though a strainer into a bowl (or directly into the tart shell), scraping with a rubber spatula to press it through.
Smooth the lemon filling into the pre-baked tart shell and pop it in the oven until the curd is just set—about 5 to 6 minutes.
Remove from the oven and let cool before slicing and serving.
(You can taste the filling after it’s made and if it’s too tangy, add up to 1/4 cup (50g) more sugar. If you find that you have a bit too much filling for your tart shell (they seem to vary), any remaining lemon filling that you don’t use can be spread on toast, fresh biscuits, or scones. You could substitute fresh lime juice for the lemon, and if you have Meyer lemons, reduce the sugar to 100g or 1/2 cup.)