In a medium heatproof bowl, whisk the lemon juice, lime juice, eggs and 1 cup (220g) caster sugar to combine. Place bowl over a medium saucepan of simmering water (make sure the bowl doesn’t touch the water). Cook, stirring constantly, for 8-12 mins or until the mixture coats the back of the spoon. Remove from heat. Cover and place in the fridge for 2 hours to chill.
Lightly grease a 5cm-deep, 23cm (base measurement) round springform pan and line the base with baking paper. Place the almond flour, almonds and remaining caster sugar in a food processor and process until the mixture resembles fine breadcrumbs. Add the oil and a pinch of salt and process until combined. Press almond mixture evenly over the base and up the side of the prepared pan. Place in freezer until firm.
In the bowl of a stand mixer fitted with a whisk attachment, beat cream cheese and ½ cup (80g) icing sugar on medium speed for 5 mins or until light and fluffy. Beating on low speed, add 2 cups (500ml) cream in a thin, steady stream until smooth. Increase speed to medium and beat until stiff peaks form.
Spoon half the cream cheese mixture evenly over the almond crust in the pan. Top with half the lemon mixture. Spoon over the remaining cream cheese mixture and use a small round-bladed knife to gently marble. Cover the remaining lemon mixture and place in fridge. Place cheesecake in the fridge for 4 hours or until firm. Carefully transfer cheesecake to a platter. Freeze for 2-4 hours or until semi-frozen.
Use an electric mixer to whisk the remaining cream and icing sugar in a bowl until stiff peaks form. Spoon over the cheesecake. Stir remaining lemon mixture to loosen and drizzle over the cheesecake. Serve immediately.
Tip: SERVE WITH... lemon zest and lime zest