1) Combine all of the ingredients in a large microwave-safe bowl. To avoid bubble-overs, the contents should fill no more than 1/4 of the bowl; an 8-cup measure works well here.
2) Microwave the ingredients in 1-minute increments, removing from the oven and stirring to combine after each minute.
3) When curd starts to thicken; coats the back of a spoon; and starts to mound a bit as you stir, it's done. This will take anywhere from 4 to 10 minutes, depending on the strength/power of your microwave. The curd's temperature should have reached at least 185°F.
4) Stir the curd one more time, spoon it into a storage container, and refrigerate until firm.
5) Keep curd refrigerated for up to 3 weeks; freeze for longer storage.
Yield: a scant 2 cups lemon curd.