Heat oven to 190C/170C fan/gas 5.
To make the crumble, mix the flour,
ground almonds and sugar in a bowl,
then rub in the butter as though you
are making pastry. Tip the mixture onto
a large baking tray and spread out evenly.
Create little clumps in the mixture by
pinching it together with your fingers,
then bake for 10 mins.
Meanwhile, make the fruit layer. Mix
the sugar and cornflour together in a
large bowl, then toss in the berries and
rhubarb until well coated. Tip the mixture
into a pan and cook over a gentle heat,
stirring until the fruit softens a little and
any released juices thicken.
Tip the fruit mixture into an ovenproof
dish, scraping in all the thickened juices.
Add the flaked almonds to the crumble
mixture, then scatter over the top. Bake
for 20 mins until the fruit is tender and
the crumble golden. Leave to cool
slightly, then serve warm with vanilla
ice cream, if you like.