Heavily coat a popover pan with cooking spray, and set aside.
Combine flour and remaining ingredients in a large bowl; stir with a wire whisk until smooth.
Pour batter evenly into prepared pan.
Place in a cold oven. Turn oven on 450, and bake 15 minutes. Reduce heat to 350, and bake an additional 35 to 40 minutes or until popovers are crusty and brown.