Separate the yolks and whites. Transfer the egg yolks to a large bowl (see Note 2) and keep the egg whites in a small bowl at room temperature for the meringues.

Using the hand mixer on high speed, beat egg yolks until they triple in volume and become very pale yellow and thick. It will have almost a pudding consistency. This will take 10 to 15 minutes of consistent beating.

Add the room-temperature mascarpone to the eggs and beat with a hand mixer until smooth and creamy. Don’t overwork the mixture.

Add the corn syrup to a glass measuring cup. Microwave for 1 minute until the corn syrup boils. Remove from the microwave and let stand until the bubbles die down, about 1 minute.

Turn the mixer to medium speed and beat the eggs and mascarpone while slowly drizzling in the warm corn syrup. Continue mixing for 5 minutes until the mixture begins to cool. The eggs will take on more volume as the warm liquid mixes into the mixture.

Add the espresso, ½ cup heavy cream, roughly chopped dark chocolate, and vanilla extract in the same glass measuring cup. Microwave in 30-second increments until the chocolate melts. Remove from the microwave and stir to create a smooth mixture.

With the mixer on, drizzle the dark chocolate mixture into the bowl. Continue mixing for 6 to 7 minutes until the mixture cools down and is thoroughly combined.

Remove the whipped cream from the fridge. Add half to the mixture and gently fold it with a rubber spatula until combined.

Add the rest of the cream and fold it in until combined. Do not over-mix the mousse. It may seem a little runny.

Preheat oven to 250ºF. Line two baking sheets with parchment paper.

Place the reserved egg whites in a large bowl. Add ¼ teaspoon cream of tartar and ⅛ teaspoon salt. Beat with an electric mixer on medium speed until foamy, about 3 minutes.

Begin adding the sugar 1 tablespoon at a time, beating at high speed after each addition until the sugar dissolves. Continue beating the egg whites until they become thick and glossy. Once the eggs reach stiff peaks, turn off the mixer. This requires 10 to 12 minutes of consistent mixing.

Attach a star tip to a pastry bag. Transfer the meringue mixture to the bag. Pipe the meringues into 1-inch-diameter circles directly onto the parchment paper, about 1 inch apart. Since the cookies won’t spread in the oven, they don’t need much space between them.

Transfer the sheet pans to the preheated oven for 1 hour. Turn off the oven and open the door slightly. Allow the meringues to cool down gradually for 1 hour.

Remove the meringues from the oven and let them stand for 30 minutes. Then, gently remove them from the baking sheet and transfer them to an airtight container until ready to serve the mousse.

Remove the serving glasses from the fridge and spoon a few raspberries on top. Garnish with the meringues. Enjoy!