Whisk the cornstarch and 2 tablespoons water in a 4-cup (960 ml) glass measuring cup until smooth.
Use a wooden spoon to stir in an additional ⅓ cup (80 ml) water, the blueberries and honey until well mixed. Microwave on high for 2 minutes; stir. Microwave for 2 to 4 minutes longer or until thickened and translucent, stirring every 2 minutes. Stir in the lemon