preheat oven to 450. Whisk together dry ingredients
2
Add shortening to mixture, breaking up by hand into small flakes. Add butter, also in small pieces, tossing into mixture, and pressing into small, flat bits. Freeze for about 15 mins.
3
Prepare work surface with flour and non-stick cooking spray
4
Add buttermilk to mixture (reserve about 2 tblsp, and use if still dry) stirring with fork, until mixture comes together, dough will be slightly sticky
5
Form a dough lump, transfer to work surface and roll to 10 x 10 in sq. fold dough into thirds, then in half, then roll out to 1/4 in thickness. cut out 3" rounds of dough (approx. 9), reform remaining dough into ball, and repeat above (approx 3)
6
Brush tops with additional melted butter if desired. Bake for 15-17 min. on lower middle rack