A delightful and tangy lemon butter spread, perfect for desserts or as a topping.
Zest the lemons to get about 2 teaspoons of zest, then juice them to obtain half a cup of juice.
Use a microplane zester for fine zest and roll the lemons before juicing to extract more juice.
In a heatproof bowl, combine the lemon zest, juice, sugar, and eggs, whisking until smooth.
Ensure the eggs are at room temperature to mix more evenly.
Place the bowl over a saucepan with simmering water, ensuring the bottom of the bowl does not touch the water.
This method prevents the mixture from curdling by providing gentle, even heat.
Cook the mixture, stirring constantly, until it thickens to a custard-like consistency, about 10 minutes.
Stir continuously to avoid lumps and ensure even cooking.
Remove from heat and stir in the butter until fully melted and incorporated.
Add the butter in small pieces to help it melt more quickly and evenly.
Transfer the spread to a clean jar and let it cool before storing in the refrigerator.
Cover the surface with plastic wrap to prevent a skin from forming.