Use a large baking tray; spray with non-stick cooking spray. Preheat oven to 220 degrees C .
Place the flour, baking powder, bicarbonate of soda and the salt and cayenne pepper in a large bowl. Cut in butter with 2 knives until the mixture resembles coarse crumbs. Stir in the oil, buttermilk and sunflower seeds and mix to a soft dough; do not overmix.
Drop the dough in heaped tablespoons 5 cm apart onto the baking tray. Bake for about 12 minutes or until golden brown and crusty.
As well their use in the production of polyunsaturated oil, sunflower seeds are also roasted and ground to make a flour, which is available from health food shops.