OK - from Leith's Baking Bible, p. 140:
Filling:
12 Victoria plums or similar, halved and stoned, then cut into quarters
140g blackberries
30g soft light brown sugar
2 tbs cornflour
½ tsp ground cinnamon
Topping
170g plain flour
Pinch salt
2 tsp baking powder
½ tsp bicarb
85g butter
45g caster sugar
100 ml plain yoghurt
Extra caster sugar for sprinkling
Oven 200C/GM6
Put plums in a bowl with blackberries
Mix together sugar, cornflour and cinnamon. Toss with fruit. Place fruit into shallow ovenproof baking dish with diameter about 17cm
Topping. Sift flour with salt, baking powder & bicarb into a large bowl. Rub in butter. Stir in sugar.
Stir yoghurt in to make soft light dough. Turn out on to a floured work surface and pat into 1cm thick disc. Cut into 3.5 cm rounds using floured scone cutter. Place ?cobbles? onto the fruit, slightly overlapping. Sprinkle with caster sugar.
Bake in top third of oven for 30-35 mins until fruit is bubbling and topping golden brown. Serve warm
NB. I didn?t have yoghurt, so used 100ml milk and added 1 tsp cream of tartar to flour mix. Worked well, but the dough was quite sticky, so I had to add a bit more flour when it was turned out.
Also, when you think it?s cooked, stick a knife in the middle to make sure the dough is cooked through.