1 loaf Italian bread, torn into large pieces
2 cups frozen blueberries, divided
1-1/2 cups mascarpone cheese
1/2 cup sugar
8 eggs
1 cup sour cream
1 teaspoon vanilla extract
1/2 teaspoon ground cinnamon
2/3 cup milk
Grease a 9-by-13 casserole dish.
Place half of the bread pieces inside the casserole dish and sprinkle with half of the blueberries. Top with remaining bread pieces.
In a large bowl, beat the mascarpone cheese and sugar until smooth.
Beat in the eggs, sour cream, vanilla and cinnamon.
Gradually add milk to the egg mixture until well blended. Pour this mixture over the bread and blueberries in the casserole dish.
Cover the casserole dish with plastic wrap and place in the refrigerator overnight.
In the morning, remove the casserole from the fridge and let it sit out for about 30 minutes.
Meanwhile, preheat oven to 350 degrees F.
Remove plastic wrap from the casserole and replace with aluminum foil. Place the casserole into the oven and let it cook for 30 minutes.
Remove the foil and bake for another 25 minutes, or until a knife inserted into the center comes out clean.
Let casserole sit for about 5 minutes before slicing and serving.