What can I use to thicken baby formula?

Nectar Thick: Use 1 ½ teaspoons of dry infant cereal (rice, barley, oatmeal, mixed) for EACH ounce of formula. Infant cereal must be ground up or pulverized. Do NOT use flake cereal. Honey Thick: Use 2 ½ teaspoons of dry infant cereal (rice, barley, oatmeal, mixed) for EACH ounce of formula.