Mandarin and Ruby Red Grapefruit Tiramisu

Cut the ruby grapefruit in half. Squeeze the juice from one half and add it to the mandarin juice. Set the combined juice aside.

Peel and segment the remaining mandarin and the other half of the grapefruit.

In a small bowl, beat the thickened cream until it forms soft peaks; set it aside.

In another bowl, beat the egg yolk and caster sugar together until the mixture is fluffy and pale.

Add the mascarpone cheese to the egg yolk mixture, then gently fold in the whipped cream until you have a soft, light mixture.

In a separate bowl, beat the egg white until it forms soft peaks, then fold it into the mascarpone mixture. Finally, fold the mandarin zest through the cream.

To assemble, dip each savoiardi biscuit into the citrus juice for about 2 seconds per side. Break each biscuit in half and arrange the pieces at the bottom of your serving glasses. Top with 2-3 tablespoons of the mascarpone cream mixture, then add a few fruit segments.

Repeat the layers: more juice-dipped savoiardi, then mascarpone cream, and finally more fruit segments. Continue this layering for all four glasses. Chill the assembled desserts for 2-3 hours before serving.