01 -
Grease a 13-by-9-inch or similarly sized baking pan.
02 -
Place the bread cubes in the prepared pan. In a large bowl, whisk together eggs, milk, sugar, lemon zest, lemon juice, and vanilla extract until well combined. Pour half of the egg-milk mixture over the bread and stir to moisten. Top with the remaining egg-milk mixture to cover completely.
03 -
Cover the pan and refrigerate for at least 2 hours or overnight.
04 -
Preheat the oven to 350°F. Bake uncovered for 40 minutes, or until golden brown.
05 -
While the French toast is baking, combine the sugar, cornstarch, 3/4 cup water, and lemon juice in a small saucepan. Bring to a boil over medium heat. Add the blueberries and continue to boil, stirring often, until the syrup thickens and the blueberries begin to burst. Keep warm until ready to use.