Toss the frozen blueberries with flour.
Cut enough Italian or French bread into cubes, so that you have about 8 cups of bread cubes.
Whisk together eggs, milk, maple syrup, half-n-half, vanilla, cinnamon, brown sugar and granulated sugar.
Cover the bottom of a greased slow cooker (I used my 6 quart Crock Pot.) with half of the bread cubes and sprinkle with half of the blueberries. Repeat with a second layer.
Pour the egg mixture over the everything.
Gently stir so that the bread soaks up the egg mixture.
Cook on low for 3-4 hours.