Preheat oven to 400. Spray the bottom of a 13 x 9 pan pan. Melt the stick of butter and mix it with the brown sugar. Pour the mixture on the bottom of the pan. Spread. Layer the Texas Toast (about 6 pieces) in the pan. Sprinkle cinnamon on top of the bread. Then put another 6 slices to make a new layer. Sprinkle cinnamon on top. Beat eggs and milk together, then pour over the bread as evenly as you can. If the mixture pools, you can take a butter knife to spread it across. Cover with foil and bake for 30 minutes.
(You can also make this ahead and refrigerate overnight to cook in the morning.)