Combine flour, sugar, baking soda, baking powder and salt in a large bowl. Whisk until combined.
Cut 9 Tbsp. of the cold butter into cubes. Work the butter into the dry mixture using a pastry blender, food processor or your hands.
Pour in the buttermilk, halved cranberries and orange zest. Mix to combine.
On a floured surface, work the bisconie dough together with your hands until a soft dough forms. Roll the dough out to a thickness of 1 inch. Cut 3-inch circles in the dough, using a biscuit cutter or a glass. Reroll the scraps and repeat as necessary.
Transfer the bisconies to a parchment lined baking sheet.
Melt the remaining 2 Tbsp. of butter in a small bowl that is microwave safe. Brush the bisconies with the melted butter. Sprinkle with turbinado sugar. Bake in the preheated oven for 30-35 minutes.
Cool on the baking sheet for 5-10 minutes before transferring to a wire rack.