| 1 | Preheat the oven to 450°F (500°F for convection). | 10 min |
| 2 | Combine flour, cream of tartar, baking soda, and salt in a large mixing bowl. | 2 min |
| 3 | Cut the cold butter in the dry ingredients with a pastry blender until the mixture resembles coarse crumbs. Refrigerate for 20 min if the butter gets soft during this process. | 2 min
(20 min) |
| 4 | Add 1½ cups of buttermilk, stirring enough to moisten the ingredients (adding more 1 tbsp at a time, if needed). | 2 min |
| 5 | Being careful not to overwork the dough, kneed the dough 10 times on a lightly floured surface or until the dough just holds together. | 3 min |
| 6 | Roll or pat out into a 14×10" rectangle. | 1 min |
| 7 | With the short side nearest you, spread 3 tbsp of the softened butter over the ⅔ of the surface furthest from you. | 1 min |
| 8 | Fold the dough in thirds (like a letter) by pulling the bottom over the center and then the top third over that. Expect the dough to crack during this process. | 1 min |
| 9 | Pat back into a 9×12" rectangle and repeat the same process twice more with another 3 tbsp of the softened butter each time. | 2 min |
| 10 | Pat the dough out into a 1" thick rectangle. | 1 min |
| 11 | Cut the dough into 2-3" squares using a scraper and place on a lightly oiled cooking sheet about 1" apart. Brush the tops with the melted butter. | 1 min |
| 12 | Place in the oven and bake until the tops are golden brown and firm. | 10-12 min |
