Heat oven to 200C/180C fan/gas 6.
Tip the plums into a bowl. Toss with the
spice, 50g of the sugar and a small pinch
of salt, then set aside to macerate.
Gently melt the butter in a saucepan.
In a large bowl, mix the oats, flour, walnut
pieces and remaining sugar together,
making sure there are no lumps of sugar,
then stir in the butter and golden syrup
until everything is combined into a loose
Grease a square baking tin about
20 x 20cm. Press half the oaty mix
over the base of the tin, then tip over the
plums and spread to make an even layer.
Press the remaining oats over the plums
so they are completely covered right to
the sides of the tin. Bake for 45-50 mins
until dark golden and starting to crisp a
little around the edges. Leave to cool
completely, then cut into 18 little bars.
Will keep in an airtight container for 2
days or can be frozen for up to a month.