Sift the flour and baking powder together. Grease a 12-hole muffin tray lightly with corn oil and preheat oven to 200°C. Put sifted dry ingredients in a mixing bowl. Stir in sugar, salt, currants and oats.
Combine milk, egg and melted butter in a small bowl. Add to the flour mixture. Mix in quickly and thoroughly with a wooden spoon.
Spoon mixture into prepared muffin tray and bake for 15-25 minutes or until muffins are well risen and golden brown. Serve the muffins hot.