-
Liberally spray a 9 x 13 baking dish with cooking spray. Lay out 6 of the slices of the bread in an even bottom layer in the pan. In a bowl, stir together the softened mascarpone cheese, balsamic vinegar, vanilla and pumpkin pie spice. Evenly distribute the mascarpone mixture onto each slice of bread and smooth it out. Finish each sandwich with another slice of bread on top.
-
In a mixing bowl thoroughly whisk together the milk, pumpkin butter, eggs, vanilla, pumpkin pie spice, cinnamon and nutmeg. Pour the custard all over the sandwiches and make sure they get pretty submerged by gently pressing the sandwiches down. Cover the baking pan and let it sit in the refrigerator overnight.
-
In the morning, pre-heat the oven to 350F. Get the pan of custardy sandwiches into the oven to bake for 45-50 minutes, until the bread is golden and crisp on the edges and the egg mixture is set. Take it out and let it cool for a couple of minutes.
-
Cut out and plate each sandwich with all of that gorgeous custard on it with the super gooey and creamy middle. Dust the top of each sandwich with powdered sugar and serve!