Lightly grease an 18 cm/7 in
loose-bottomed cake tin (pan). Sift the flour into a bowl. Add the
butter and rub in with the fingertips. Stir in 75 g/3 oz of the sugar.
Spoon about a third of the mixture into a separate bowl and reserve.
Knead the remaining mixture until it forms a ball. Press into the base
and sides of the tin. Put the halved plums in the tin and sprinkle
with the remaining sugar. Scatter the crumble over, then add the
almonds. Cook in a preheated oven at 190°C/375°F/gas mark 5 for about
40 minutes until crisp and golden. Leave to cool for 10 minutes, then
carefully remove from the tin but leave on the base. Serve warm or
cold with Chantilly Cream.