1Heat oven to 450°F. Lightly grease rack in roasting pan with vegetable oil or shortening. Rub pork with pepper and salt; place on rack in roasting pan. Roast 20 to 25 minutes or until pork has slight blush of pink in center and meat thermometer inserted in center reads 145°F. Let stand 10 minutes. Cut into thin slices; cover to keep warm. Reduce oven temperature to 425°F.
2Meanwhile, lightly spray cookie sheets with cooking spray. In large bowl, mix yeast, sugar and warm water; let stand 5 minutes. Add Bisquick mix, pecans, buttermilk, butter and pesto to yeast mixture, stirring until dry ingredients are moistened. Stir in flour as needed (up to 1/2 cup) until dough pulls away from side of bowl. On lightly floured surface, gently knead dough 2 to 3 times. Pat or roll dough to 1-inch thickness; cut with 1 1/2-inch round cutter. Place biscuits on cookie sheets.
3Bake 10 to 12 minutes or until lightly browned. Split biscuits; serve sliced pork in biscuits with mustard.