Heat oven to 180C/160C fan/gas 4.
Dissolve the baking powder in the milk.
Beat the butter and sugar until pale and
creamy, then mix in the oats, flour, raisins,
walnuts and milk to make a stiff dough.
Tip the dough onto lightly floured
surface and roll out until about 1cm thick.
Cut into circles with a 5cm pastry cutter,
place on an oiled baking sheet, then bake
for 15 mins until lightly golden. Leave
to cool, then serve with cheese. Can
be baked up to 2 days ahead and kept
in an airtight container until serving.