First, the Lemon Curd
makes about a pint

3 large eggs
3 large eggs yolks
1/2 cup sugar
zest of 1 lemon (strip the lemon of zest before you juice, or you’ll be desperately trying to scrape zest off lemon peels, like I’ve been caught doing)
1/2 cup lemon juice (if you want this to taste fresh and vibrant, not chemically and processed, you MUST squeeze your own lemons. Five or six lemons should do it. Taking the time is beyond worth it.)
pinch of salt
2 sticks (8 oz) unsalted butter, cut up into small pieces

First, make the curd:
1. First gather all your ingredients. 
2. Fill a medium pot with a couple of inches of water and bring to a boil. We’re going to improvise a double boiler.
3. Pour the eggs, sugar, lemon zest, lemon juice and salt into a large bowl. (Keep the butter chilled.) Whisk it up.
4.  Set the bowl over the pot with boiling water. This is our faux double boiler.
5. Now whisk like a hurricane, fast and furious. You must whisk the entire time the bowl is over the water. Keep the mixture moving, so the eggs don’t get a chance to scramble. After a few minutes (five?) it starts to get frothy. (If necessary, hold the bowl still by gripping the edge with a kitchen towel.)
6. Keep on whiskin’. After a few more minutes (five more?), it transforms into something creamy. Whisk for another minute just to thicken it up.
7. Take the bowl off the heat. Feed it a handful of butter and whisk it in. The residual heat of the curd will melt it. Keep adding handfuls of butter until it’s all in and fully incorporated. If you still see any little lumps, return to the double boiler for a brief minute, until they disappears, but this is rarely necessary. 
8. Push the curd though a fine mesh sieve to remove the stray bits of scrambled egg that didn’t cooperate. 
9. Put a piece of plastic wrap directly on its surface to prevent a skin from forming and refrigerate. Once it’s completely cold, wrap the whole container tightly and store. (The curd will firm up considerably as it cools. Give it a good stir to loosen it up again before using.) You can store it in the fridge for up to 5 days or freeze for up to a month. To defrost, let the container thaw in the fridge overnight.

Perhaps make it into mousse?
1 cup heavy cream
1/4 cup sugar
1 1/2 cups lemon curd (recipe above, in case you missed it)

1. In a medium bowl, whisk together the sugar and heavy cream to soft peak stage.
2. Because we whipped air into the cream and made it light and delicate, and because the curd is heavy and dense, we will fold the cream into the curd gradually, so we don’t completely deflate the cream. Scoop a third of the whipped cream into the bowl with the curd. You can eyeball this. It doesn’t have to be exact. Gently fold it in. 
3. Scrape in the rest of the heavy cream and fold it in.
4. Spoon into pretty wares. This can be served right away, or refrigerated for up to 8 hours.