Grease a 9 x 13 baking pan with butter or cooking spray
Slice then cut bread into cubes, about 1 inch in size. Put cubes into large bowl and set aside.
Whisk eggs, the 2 ¼ half and half, cinnamon, nutmeg, brown sugar and vanilla together until no brown sugar lumps remain. Pour over the cubed bread and push cubes down into egg mixture until all the cubes have soaked it up.
in a small bowl mix your cream cheese layer by adding your cream cheese, powdered sugar, vanilla and half and half. Mix well until well blended. You want the cream cheese to be spreadable, so adjust the amount of half/half as needed.
Pour half of the cubed bread/egg mixture into your baking pan
drop by spoonfuls your cream cheese mixture, and spread over layer of bread/egg mixture
top with your blueberries - I normally sprinkle them with a cinnamon/sugar mixture to sweeten a bit
add the remain cubed bread/egg mixture. Cover the pan tightly with plastic wrap and put in the refrigerator for at least 3 hours - overnight is better.
Streusel Topping - Whisk together the brown sugar, flour, and cinnamon in a medium bowl. Add this mixture to a food processor with a chopping blade. Add the cold butter and pulse until the butter is combined with the dry ingredients and it forms clumps. If you don't have a food processor, you can use two forks to cut the butter into the dry ingredients. If making this ahead, you can store in a plastic storage bag until ready to bake the french toast.
Preheat oven to 350°F. Remove pan from refrigerator. Cover with tin foil that has been sprayed with non-stick spray - make sure to do this or your tin foil will stick to your french toast.
Bake for 30 minutes. Take out of oven, remove tin foil, and top with your streusel topping. Return to the oven and continue baking an additional 15- 25 minutes. I usually do mine around 45-50 because I like it to be softer - more the consistency of bread pudding. However, if you like yours set a bit more, just bake it a bit longer.