Tip the rhubarb into a bowl and sprinkle
over 50g of the sugar. Stir so the rhubarb
is covered, then set aside for 30 mins to
draw out some of the juices (macerate).
Meanwhile, grease and line the base and
sides of a 23cm loose-bottomed, round
cake tin with baking parchment and heat
oven to 180C/160C fan/gas 4.
Tip remaining sugar, the butter, orange
zest and juice into a large bowl and beat
with an electric whisk until well blended.
Add the flour, almonds, baking powder
and eggs, then beat again until smooth.
Fold in the rhubarb and any juices. Spoon
into the tin and level the top.
Sprinkle with the flaked almonds,
then bake in the centre of the oven for
1 hr-1 hr 15 mins until risen, golden and a
skewer inserted into the centre comes
out clean. Cover with foil if the cake starts
to brown too much during cooking. Leave
in the tin for 15 mins before removing and
cooling completely on a wire rack. Dust
with a little icing sugar before serving.