Spoon into the remaining two prepared tins then bake all three for 40 minutes.
Whilst the cakes are in the oven, make the syrup; heat the water and sugar in a small saucepan until the sugar is completely dissolved.
Let it simmer for 2-3 minutes then add the vanilla essence and leave to cool.
Remove the cakes from the oven when ready - insert a thin skewer into the sponge and if it comes out clean, the cake is done. Leave to cool for 5 minutes.
Whilst the cake is still warm but not hot, brush each one with the sugar syrup.
Do not soak the sponge, just make sure you get a nice even coverage that goes all the way to the edges.