First make the blackberry sauce to
ripple through the mallow. Put the berries
and 1 tsp sugar in a small bowl and cover
with cling film. Microwave for 30 secs on
High. Alternatively, add 1 tsp water then
soften in a pan over a low heat. Mash
well until saucy, then leave to cool.
Heat oven to 160C/140C fan/gas 3.
Grease and line the base and sides of a
23cm square traybake tin, leaving some
overhang. Using electric beaters or a
hand whisk, beat the butter and sugar in
a large bowl until very pale and creamy,
then beat in the egg and yolks, followed
by the vanilla. Mix the flour, almonds,
baking powder, nutmeg and a pinch of
salt, then fold into the fluffy mix to make
a very thick batter.
Fold in the apple, then spoon into the
tin and smooth over the top. Scatter with
the blackberries, poke them in just a
little, then bake for 45 mins until golden
and a skewer inserted into the middle
comes out clean. After removing, leave
the oven on.
For the mallow topping, you’ll need a
large piping bag with a 1cm nozzle, or a
food bag with a corner snipped off. Whisk
the egg whites, lemon juice and a pinch
of salt to stiff peaks. Add the sugar
1 tbsp at a time, whisking well after each
spoonful, to make a shiny, stiff meringue.
Ripple with the cooled blackberry mix,
then spoon into the bag. Pipe 16 evenly
spaced, walnut-sized meringues on top
of the cake (you’ll have some left over),
scatter with the toasted almonds, then
bake for 10-12 mins until the meringues
are just set. Cool in the tin for 30 mins,
then remove to a rack to cool completely.
Add a dusting of icing sugar, if you like,
then cut into squares.