Cut 30 pieces of foil, each 6 inch square. Stir together masa flour and chicken broth to make a thick paste. Place about 1 1/2 tablespoons of the paste on each foil square and spread in center of foil in a 3 inch square.

Mix together corn, olives, onion, and salsa. Place about 1 1/2 table-spoons of filling down center of each masa square. Fold foil edges together so masa edges meet, then seal all sides.

Arrange tamales in a kettle with a rack placed on the bottom, so that the tamales are not in the water. Add about 1 inch of water, cover, and steam about 45 minutes. About 6 servings.