Spray an 8x8 baking dish with oil and preheat oven to 375 degrees Fahrenheit.
In a medium bowl, whisk together the eggs, milk, salt, cinnamon, maple syrup, and vanilla. Coat each slice of bread in this mixture and layer them on the prepared dish. In the remaining liquid, add the blueberries then pour on top of the dish. Bake for about 30 minutes, until all the liquid is absorbed. Enjoy!