Sprinkle a small amount of baking soda onto the orange stain on the cooktop. Use a little less than a teaspoon.
Squirt a small amount of dish soap onto a damp sponge.
Rub the baking soda into the stain with the sponge and soap. The baking soda should be abrasive enough to scrub away the stain from the cooktop, and the soap will help remove any grease left from the stain.
Rinse the sponge in water then wipe away the soap and baking soda from the cooktop to remove any residue left from the stain.