Prepare the Lemon Ingredients

1. Zest the Lemons: Using a fine grater or zester, zest the Meyer lemons, being careful to avoid the bitter white pith.
2. Juice the Lemons: Squeeze the juice from the lemons until you have about 1/2 cup of lemon juice. Make sure to strain out any seeds.

Cook the Curd

1. Combine the Ingredients: In a medium saucepan, whisk together the lemon juice, lemon zest, sugar, eggs, and salt. Place the saucepan over medium heat.
2. Stir Constantly: Cook the mixture, whisking constantly, for about 10-15 minutes, until it thickens and reaches a custard-like consistency. Be sure to stir the entire time to prevent the eggs from curdling.
3. Test the Thickness: To check if the curd is ready, dip a spoon into the mixture. If it coats the back of the spoon and you can run your finger through it to leave a trail, it’s done.

Finish the Curd

1. Add the Butter: Once the curd has thickened, remove the pan from the heat. Stir in the butter, one piece at a time, until fully incorporated and the curd is smooth.
2. Strain the Curd (Optional): For an ultra-smooth curd, strain it through a fine mesh sieve to remove any bits of zest or egg solids.

Cool and Store

1. Cool the Curd: Let the curd cool to room temperature, then transfer it to a clean jar or container.
2. Refrigerate: Store the curd in the refrigerator for up to 1-2 weeks. It can also be frozen for longer storage, but be aware it may lose a bit of its smooth texture upon thawing.