Combine the blueberries and 1/4 cup sugar in a medium microwave-safe bowl. Cover with wax paper; microwave at HIGH 3 minutes or until thoroughly heated and sugar dissolves, stirring after 1 1/2 minutes.
Combine 1/4 cup sugar, milk, cornmeal, and lemon rind in a 2-quart glass measure; stir with a whisk. Microwave at HIGH 7 minutes or until thick and bubbly, stirring every 2 minutes. Stir in vanilla and salt. Serve with blueberry topping.