Slice bread into 1 1/2 inch slices and lay them flat in a 9×13 inch casserole pan.
Mix eggs, milk, cinnamon and vanilla in a bowl and then pour the mixture over the bread slices.
Cover and refrigerate. After a couple of hours flip the bread slices over so they will soak up the remaining egg mixture, then let sit over night or for at least four or so hours.
Now here is where I did things a little differently, I took the soaked slices out of the pan and stacked them on a plate while I washed and dried the pan (the reason I did this was because the first two times I made this, I ended up with a layer of egg on the bottom of the pan which I did not want).
Mix the melted butter and brown sugar together and pour into the bottom of the greased casserole dish, then lay your soaked bread slices back in on top of the mixture.
Mix pecans, melted butter and brown sugar together, and then dabble over the top of the french toast slices. Bake at 350 degrees for 40-45 minutes.
To make the glaze, melt the butter in a little pan, and stir in the brown sugar. Heat to boiling while stirring, and boil for two minutes, and then stir in the milk and bring to a boil again. Remove from heat and let cool, then stir in the powdered sugar. I had to add more than the 1 Tablespoon of milk to get a glazing consistency especially if it sits for a few minutes. When the french toast is done baking and you are ready to serve, drizzle the glaze over each slice.