Cut loaf into cubes and place evenly in a greased 9x13 pan
Mix together eggs, milk, heavy cream, sugar and vanilla in a separate bowl. Pour evenly over bread. Cover your pan with Saran Wrap and refrigerate overnight (6-8 hours).
Mix together flour, brown sugar, cinnamon, and salt in a medium bowl.
Add the Grassland butter and combine until the mixture is crumbly. Place in a Ziploc bag and refrigerate overnight as well.
When the time has passed, preheat your oven to 350 degrees. Take the pan and Ziploc out of the freezer and spread the crumbly mixture from the ziploc over the bread. Top with blueberries
Bake for 45 minutes to an hour. The longer it stays in, the softer it will be.
Let stand for 5 minutes to cool and serve immediately.
