Add the cream cheese, mascarpone cheese, and lemon juice to a bowl. Heat gently in a double boiler, stirring the mixture until smooth.

In a different bowl, combine the egg with the granulated sugar, heat in the double boiler, and whisk until the mixture thickens.

Combine Step 2 to Step 1.

In a clean bowl, whip the heavy cream until stiff peaks form.

Add Step 3 to Step 4.

Spoon the mixture into whatever container you prefer, and chill in the freezer to set (if you use plastic containers, wrap in aluminum foil so the plastic doesn't crack).

When the tiramisu has hardened, top each cup with sifted espresso and cocoa powder (brush away any spilled powder with a pastry brush).

Garnish with fruit of your choice, or a little powdered sugar to finish.

If you add gelatin to this recipe, it will become a mousse (bloom 3 g of gelatin in 15 g of water and add this at the end of Step 5).

This recipe is for a rich, strawberry flavour unbaked cheesecake ice cream.