Gather all ingredients.

Combine lemon juice, sugar, butter, eggs, and lemon zest in a 2-quart saucepan.

Cook over medium-low heat, whisking constantly to prevent the eggs from curdling, until mixture starts to get thick and bubbles rise to the surface, about 5 to 6 minutes.

Remove saucepan from the heat; transfer lemon curd into a large bowl and place a piece of plastic wrap on top to prevent a skin forming. The curd will thicken more as it cools. Store in the refrigerator.

Serve and enjoy!