Preheat Oven to 210CGrease 12 medium muffin trays (I use cooking spray or you could use patty cases)In a large bowl combine self raising flour, salt, sugar & cheese and mix together.In a small bowl combine egg & milk and beat with a fork until well combined.Pour the wet ingredients into the dry ingredients and very gently mix them - being careful not to overmix.Spoon into the muffin trays about ¾ full or make in mini muffin trays if you wish.Bake for 10-12 minutes until muffins spring back to the touch and are a nice light golden brown.Remove from the oven and cool for 5 minutes before transferring to a wire rack to cool completelyIf they stick a little gently run a knife around the edges of the muffin to take out carefully.Enjoy warm with butter or cold in lunchboxes.