Cut both loaves of bread into 1 inch thick slices, discarding of the ends. You should get about 7 slices per loaf (14 slices total). Set aside.
In a large bowl combine your eggs, milk, vanilla extract, cinnamon, salt and nutmeg. Whisk until combined.
Line a large sheet pan with parchment paper.
Dunk each slice of bread into your egg mixture and then lightly squeeze out the excess liquid (without crushing the bread too much). Transfer soaked bread to your sheet pan. Repeat this for each slice of bread.NOTE: the cinnamon tends to rise to the top of the egg mixture so in-between each dunk, whisk your egg mixture again so that you do not have one slice soaking up all of the cinnamon. When stacking your bread onto the sheet pan, instead of laying the bread flat, sit the bread up and criss cross each slice. This allows for a crispier toast all around!
Once all of your toast is soaked and on your sheet pan, pour any leftover egg mixture over your bread. Let your toast rest in the fridge for about 1 hour to overnight (allowing the spices in the egg mixture to really soak in). You can skip this step if you are in a time crunch.
Bake your toast at 350 degrees for 25 minutes.
Take out and let cool for about 5 minutes. Dust with powdered sugar if desired.