Servings: 16 servings
5 Meyer lemons
3 egg yolks, at room temperature
⅓ cup granulated sugar
1 (8-ounce) package mascarpone cheese
2 ounces white chocolate, finely chopped, then melted in a double boiler
2 teaspoons pure blueberry extract (optional)
¼ teaspoon salt
2¾ cups heavy whipping cream
½ cup powdered sugar, to taste
1 cup bittersweet chocolate
1 tablespoon light corn syrup
2 tablespoons raw sugar
1 tablespoon Amaretto liqueur
16 fresh blueberries
6 tablespoons almonds, coarsely chopped
Making lemon curd:
Squeeze the lemon juice. Using a strainer, remove the lemon juice pulp. Place the juice in a small saucepan. Bring to a boil, then immediately lower the heat to a gentle simmer and heat for 3 minutes. The liquid should reduce to about 1-2 tablespoons of concentrated juice. Remove from the heat. Strain the mixture through a fine mesh sieve one more time so the mousse is silky.
With a handheld mixer, whisk the egg yolks with the sugar in a small stainless steel (or heat-proof) mixing bowl until you get a pale yellow foam.
Prepare a double boiler: Fill a saucepan with water, making sure the water barely covers the bottom of the stainless steel mixing bowl. I always like to add a little kitchen towel on top of the saucepan. The bowl won't jiggle and there won't be any splatter of water in your egg mixture. Bring the water to a boil, then lower the heat to a gentle simmer. Place the stainless steel bowl over the saucepan and, using the handheld mixer, start whisking the egg mixture vigorously for about 3 minutes to thicken the texture of the egg yolks. The mixture should fall like a ribbon of sauce when you lift the whisk. Add the concentrated lemon juice. Stir constantly using a silicone spatula. The mixture will thicken. Remove the saucepan from the stove. Add a pinch of salt and stir well.
Note: A way to know that the lemon curd is ready (so the egg yolks are fully cooked) is to use a digital thermometer and wait until the temperature reaches 160-175°F.
Reserve about ½ cup lemon curd for garnish.
Making lemon mousse:
In another mixing bowl, whisk the mascarpone cheese with 2 tablespoons of powdered sugar to soften it. Slowly add the lemon curd and melted white chocolate to the mascarpone cheese, adding just a little curd at a time. Add 1 teaspoon blueberry extract (if used).
Clean your handheld mixer in hot soapy water. Always make sure the beater blades are completely clean prior to whipping cream for optimum results. Rinse with cold water to ensure the blades are cold. The whipping cream should also be whipped cold. Whip 2 cups of cream (at low speed) for 2-3 minutes until creamy and smooth. Add the rest of the powdered sugar. Increase to maximum speed and keep beating for another 2-3 minutes, until it forms soft peaks.
Pour ⅓ of the whipped cream into the lemon mixture. Mix well using a silicone spatula. Pour in the rest of the whipped cream; gently fold the whipped cream to get a light and airy mousse.
For the blueberry chocolate Amaretto sauce:
Place the bittersweet chocolate, raw sugar and the corn syrup and a pinch of salt in a bowl.
In a little saucepan, bring the rest of the heavy cream to a boil and pour over the bittersweet chocolate. Add 1 teaspoon blueberry extract and Amaretto to the dark chocolate. Mix with a wooden spoon. The sauce will thicken as the chocolate melts. Set aside.
Transfer the lemon mousse to a piping bag.
Spoon about 1½ teaspoons lemon curd into each serving cup. Drizzle a bit of the chocolate sauce (make sure it's visible on the wall of the cups), then pipe the mousse to fill the cups entirely. Plastic wrap, seal and chill them in the refrigerator for at least 4 hours.
When you're ready to serve, place each lemon mousse cup on an individual serving plate and top with a fresh blueberry (as a reminder of the flavoring in the chocolate sauce) and decorate with a sprinkle of chopped almonds.
If you want a stronger citrus flavor, you could add ¼ teaspoon of pure lemon extract to the custard. I didn't because the fruit was already very fragrant and flavorful.
If you don't have cute cup props to serve the mousse in, you could use the Meyer lemon rind (count 8 servings instead) and they will do the job splendidly.
The use of light corn syrup helps the chocolate sauce maintain a beautiful texture, even once it cools down.