Add the corn cobs to a sauce pan along with 2 cups of water. Bring to a boil and reduce to a simmer and cook uncovered for 15 minutes.
Remove from heat and strain. Return the corn cob broth to the saucepan and add sugar and turmeric. Cook on medium heat 3-5 minutes or until the sugar is dissolved.
In a small bowl combine the corn starch and 2 tablespoons of water.
Once the sugar has dissolved, add the cornstarch and water mixture. Stir to incorporate and bring to a full boil to thicken.
Remove from heat and cool to room temperature to fully thicken.