Heat oven to 350°F. Spray 9-inch glass pie plate with cooking spray. In medium bowl, cut butter into Bisquick mix, using pastry blender (or pulling 2 table knives through ingredients in opposite directions), until crumbly. Add boiling water; stir vigorously until soft dough forms. Press dough on bottom and up side of pie plate, using fingers dipped in Bisquick mix, forming edge on rim of pie plate.