In 2-quart saucepan, mix remaining 1 1/4 cups milk, the cream, 1/2 cup sugar, 2 tablespoons corn syrup and the salt. Heat over medium-low heat until bubbles just begin to form around edge of pan and mixture begins to steam. Remove from heat. Beat in cornstarch-cocoa mixture with whisk until completely combined. Return to medium-low heat. Cook, stirring constantly, until mixture thickens enough to coat a spoon. Continue to cook and stir another minute. Remove from heat.