SAUTE first 3 ingredients in large skillet until crisp-tender. Add mushrooms, kale, ground burger and steak sauce; mix well. Spoon into 16 casserole dishes (or into 1 casserole dish for trial recipe), adding about 2 cups to each.
PLACE 1 ball of pie crust dough on lightly floured surface; roll out to 8-inch round. Place over 1 filled casserole dish; trim edge with sharp knife. Reserve trimmings. Repeat with remaining pie crust dough and casserole dishes. Cut decorative shapes from dough trimmings; use to decorate tops of pies. Place in sheet pans. Whisk eggs and cream until blended; brush onto tops of pies.
BAKE in 350ºF convection oven 25 to 30 min. or until golden brown.