Blueberry Cinnamon Crumb Baked French Toast

Heat oven to 350ºF. Spread cubed bread in an even layer on sheet pan. Place in the oven for 15 minutes, stirring halfway. Set aside to cool. 

Grease a 9 x 12 pan generously with butter. In a large bowl, toss bread cubes and brown sugar. Pour bread cubes into prepared pan. 

In the same bowl, combine egg, milk, heavy cream, sugar, vanilla, and salt. Using a hand mixer with whisk attachment, whisk until well combined and foamy. Pour custard over the bread. Cover the french toast with plastic wrap and refrigerate overnight. 

For the topping, in a separate bowl, whisk sugars, spices and salt into melted butter until smooth. Add flour and mix with a spatula or wooden spoon. It will look and feel like a solid dough. Press the mixture down, cover with plastic wrap and refrigerate overnight.   

Heat oven to 350ºF. Using your fingers, break topping mixture into crumbs, making sure most are around the same size. Sprinkle crumb mixture and frozen blueberries over french toast. Bake in the oven for 30 minutes, or until golden brown.