Preheat oven to 425 F / 220 C.
In a large bowl, combine flour, baking powder, baking soda and salt.
Add in cold butter and shortening and cut in until mixture is crumbly.
Add buttermilk and combine just until all flour mixture is mixed in. BE GENTLE!
Pat out very lightly on a floured board until about ½ to ¾ inch thick.
Using a biscuit cutter, or other sharp end (not a glass!*) cut out your biscuits.
Place on ungreased cookie sheet and bake in oven for 15-18 minutes until golden brown.