French Toast with Blueberry Sauce

Prepare French toast according to package directions. (We like the microwave method best)
Combine blueberries, sugar and lemon juice in a small saucepan and bring to a boil. Lower heat to a gentle simmer.
When soft and fully cooked through, add the cornstarch slurry. Continue to simmer and stir occasionally until sauce thickens. Remove from heat and allow to cool before serving.