Sift your plain flour, baking powder, sugar and salt into a bowl and give it a wee mix about. Add your butter to this and work it in with your fingertips. Creating a nice crumbly texture, a bit like breadcrumbs. Now add your bacon, chives and cheese, mixing throughout. Gradually add your buttermilk mixing between each addition with a fork. You want it to get to the point were there's no dry bits left, you don't want it too wet or dry. That's why you gradually add the buttermilk, you may need less or more.