Lemon Posset
This refreshing dessert boasts tart lemon shells filled with sweet, creamy custard. The presentation is undoubtedly elegant, but this zingy treat requires just four ingredients and minimal prep work. If you’re looking for an easy, show-stopping dessert to dazzle your family and friends, this lemon posset recipe is for you.
This recipe was written for the Arizona Republic.
What is posset?
Posset is a classic British dessert that features a chilled, pudding-like custard that’s made with boiled cream and citrus juice. Unlike traditional custard, posset requires no eggs or cornstarch to thicken; the acid from the citrus juice encourages the cream set up into a rich, satiny pudding.
For those interested, here’s the science behind it: When citrus juice is added to boiled cream, a chemical process called acidic coagulation occurs. During the reaction, the acid in the citrus lowers the pH of the cream which then causes the milk proteins to denature and clump together. As a result, the thin cream transforms into a thick, velvety pudding.
Since food chemistry does all the work, there’s little effort on your part. In fact, this recipe is virtually foolproof.
This tart-sweet posset is bright and refreshing, and it’s an excellent way to cap off any meal. Here’s what you need to make it.
- Lemons. You’ll need four lemons for this recipe, and we use both the rind (to make a shell) and 1/3 cup of the juice. When shopping, choose ripe, good-looking fruit since the rind is part of the presentation. Note: Even if you decide to serve the posset in ramekins (as instructed below), choose firm, unblemished lemons for this recipe because they will yield the best result. Pro tip: Rinse your lemons clean before slicing and scooping the flesh as this ensures the lemon shells are free from bacteria and debris before serving.
- Heavy cream. And I mean real heavy cream here, which means nothing less than 36% to 40% fat. Here’s why: The high fat content of heavy cream and heavy whipping cream prevents the acidic lemon juice from curdling the dairy and creating harsh clumps. High fat cream creates a smooth, creamy pudding. On the other hand, light whipping cream and half and half will curdle and clump and thus ruin the recipe.
- Sugar. Granulated sugar balances the acidity of the lemon juice, and it melts perfectly into the hot cream.
- Vanilla extract. A hint of vanilla extract adds warmth and depth to this posset. Use pure vanilla extract for the best flavor.
- Garnishes. Lemon posset is perfect without garnishes, but if you feel inclined, fresh berries and mint leaves add vibrant color and flavor.
What happens if your custard doesn’t set after two hours? While this is highly unlikely if you follow the instructions (and use heavy cream), there’s always a slim chance the cream wasn’t boiled long enough. Never fear, the posset can be salvaged. If your custard hasn’t set after two hours in the refrigerator, transfer the mixture back to the saucepan, add another tablespoon of lemon juice and boil for 2 minutes. Cool for 15 minutes and then chill for two hours. Again, it’s extremely unlikely this will happen, but it’s always good to have a back-up plan.
Making lemon cups is optional. Using the lemon halves as cups is the classic choice for this recipe, but it’s not mandatory. If you’d rather serve your posset in ramekins, or small glass jars, feel free. The recipe doesn’t change at all. Pro tip: To ensure the cream mixture sets up in two hours, spoon the posset into individual portions (ramekins, small jars) before refrigerating.
How to prep ahead. Since this lemon posset recipe requires two hours of chilling before serving, it’s an ideal prep-ahead dessert for entertaining. To prep ahead, follow the recipe as instructed and, after the cream mixture has set, cover the lemon halves (or ramekins) with plastic wrap and refrigerate for up to 2 days.
How to store leftovers. Transfer leftover filled lemons and ramekins to an airtight container or cover with plastic wrap and refrigerate for up to 5 days. Note that after 5 days the custard mixture may start to separate. I do not recommend freezing this lemon posset since the custard with turn icy and then grainy when thawed.
Lemon Posset
Ingredients
- 4 lemons, rinsed clean
- 2 cups heavy cream, or heavy whipping cream
- ⅔ cup granulated sugar
- ⅓ cup fresh lemon juice, from the lemons above
- ¼ teaspoon vanilla extract
- Fresh berries for serving, optional
- Fresh mint leaves for serving, optional
Instructions
- Slice the lemons in half lengthwise.
- Run a sharp paring knife along the inside of the rind, loosening the flesh from the white pith.
- Using a spoon or your fingers, remove the flesh from the rind, creating eight lemon cups.
- Press the lemon flesh through a citrus squeezer or fine mesh sieve until you have 1/3 cup of lemon juice. Set aside.
- Combine the cream and sugar in a medium saucepan.
- Set the pan over medium-high heat and bring to a boil, stirring constantly.
- Boil for 5 minutes, stirring occasionally and keeping a close watch – reduce the heat if necessary to prevent the cream from boiling over.
- Remove the pan from the heat and stir in the lemon juice and vanilla.
- Let stand for 15 minutes to cool.
- Stir the cream again, then spoon the mixture into the lemon cups (or small ramekins). If you have leftover lemon cream, spoon it into small ramekins or glass jars.
- Refrigerate for 2 hours, until set.
- Garnish with berries and mint (if using) and serve.