Add the egg yolks and 2 tablespoons of caster sugar to the blender. Mix for 4 minutes on medium speed until pale and fluffy. Add mascarpone and vanilla and blend on medium speed until just combined. Transfer mixture to a large bowl.
In a separate bowl, whisk the egg whites until soft peaks form. Add the remaining tablespoon of caster sugar and whisk for a further 2 minutes until glossy and firm. Gently fold the egg whites into the mascarpone mixture to form a smooth cream.
Add jam to a small saucepan with 1/2 cup water. Whisk over low heat until simmering then remove from heat. Add Cointreau and stir to combine.
Dunk half the biscuits into the warm jam syrup and line the base of your serving dish (roughly 22cm diameter). Cover biscuits with half the cream then a layer of sliced strawberries.
Repeat the biscuit layer and drizzle any remaining jam syrup over the biscuits. Top with remaining cream and tightly seal bowl with cling wrap. Refrigerate for at least 4 hours or overnight. Prior to serving garnish tiramisu with a final layer of fresh strawberries.