01 - Grease a 9 x 13 inch baking dish. Spread half of the bread cubes in an even layer across the bottom.
02 - Scatter cream cheese cubes and half the blueberries evenly over the bread. Top with remaining bread cubes and blueberries.
03 - In a mixing bowl, whisk together eggs, milk, cream, sugar, and vanilla until well combined. Pour the mixture evenly over the bread and berries, pressing gently to ensure all bread pieces absorb the liquid. Cover and refrigerate for at least 30 minutes, or overnight for optimal results.
04 - Preheat oven to 350°F.
05 - In a small bowl, combine butter, brown sugar, flour, cinnamon, and salt. Mix with a fork until crumbly texture forms.
06 - Sprinkle streusel evenly over casserole. Bake uncovered for 40 to 45 minutes until golden brown and set in the center.
07 - Cool slightly before serving. Dust with powdered sugar if desired.