Sterilise the jam jars.
Slowly melt the sugar with lemon juice, zest, and 45ml of water in a pan.
Stir in the strawberries.
Boil the mixture until it reaches 105°C.
Skim froth and let the jam cool slightly.
Seal the jam in the sterilised jars.
Preheat the oven to 190°C and grease two 23cm tins.
Beat the butter, sugar, and vanilla until fluffy then add eggs.
Fold in the flour and pour into tins.
Bake for 20-25 minutes until golden.
Cool the cakes on a wire rack.
Whip the cream with icing sugar and fold in berries.
Boil 250g sugar and 125ml water to 121°C.
Whisk the egg whites with lemon juice to firm peaks.
Remove the syrup from the heat at 121°C.
Slowly whisk the hot syrup into the egg whites.
Continue beating until the meringue is tepid.
Halve the sponges to create four layers.
Layer the sponge with jam and strawberry cream.
Repeat layering until all four sponges are used.
Cover the whole cake with Italian meringue.
Texture the meringue with a fork and garnish with holly.