1-First step: Get your ingredients ready Start by measuring out 1 cup sugar, 1/2 cup lemon juice, 2 egg yolks, 3 large eggs, and 4 ounces salted butter cut into cubes. Finely grate the zest from 2 lemons and set it aside for later. If you are using unsalted butter, have a pinch of salt ready, about 1/8 teaspoon. This quick prep makes the rest of the recipe easy. It also helps you move fast once the microwave starts doing the heavy lifting.

2-Second step: Whisk the base until smooth In a large microwave-safe bowl, whisk together the sugar, eggs, egg yolks, lemon juice, and salt if needed. Keep whisking until the mixture looks smooth and even. This step matters because it helps prevent scrambled egg bits later. The mixture may look thin at first, and that is completely normal. You are building the base before the butter and heat turn it into curd.

3-Third step: Add the butter cubes Drop the butter cubes into the bowl and spread them out a little if they clump together. The butter melts during cooking and gives the curd its rich, creamy body. Salted butter works well here, but unsalted butter is fine too if you add that small pinch of salt. If you are making this for a dairy-free guest, this is the point where a plant-based butter substitute would go in a test version. The texture may be a bit softer, but the lemon flavor still shines.

4-Fourth step: Microwave in short bursts Microwave the mixture on high power for 45 seconds, then remove the bowl and stir vigorously with a whisk. This first stir helps distribute the heat and keeps the eggs from cooking too quickly in one spot. Return the bowl to the microwave and continue cooking in 45-second intervals, whisking after each round. Depending on your microwave power, this usually takes about 4 to 7 minutes total. A stronger microwave may finish faster, while a lower wattage machine may need a little more time. If you are not sure about your microwave, watch the mixture closely and stir well every time.

5-Fifth step: Check for doneness Microwave Lemon Curd is ready when it coats the back of a metal spoon or reaches 175°F on a thermometer. That temperature matters because it tells you the eggs are cooked safely and the curd is thick enough to set as it cools. The curd should look glossy and slightly thick, not watery. If the mixture still looks thin, give it another short burst and stir again. If you see small lumps, do not panic. You can strain the curd through a fine-mesh strainer for a smoother finish.

6-Sixth step: Add zest and finish Once the curd is cooked, remove it from the microwave and whisk well. Stir in the lemon zest at the end so the fresh citrus flavor stays bright. This final touch makes the flavor pop and gives the curd a fresh homemade feel. Let it cool to room temperature. It will thicken as it cools, so do not worry if it seems a bit loose right after cooking. Cover it and store it in the refrigerator once it is no longer warm.

7-Seventh step: Serve it your way When chilled, the curd is ready to use. Spread it on toast, spoon it over pancakes, layer it into cakes, or serve it with fresh fruit. It also works beautifully on waffles, ice cream, or as a tart filling.