In your microwavable mug, mix together the egg, milk, syrup, cinnamon, and salt until all combined.
Cut off the sides of the bread (crusts) and slice your bread into square bite-sized pieces. Add the bread to the mug and press them down so they are submerged within the liquid and the bread soaks in the egg mixture.
Add the chocolate chips to the mug and give a little stir to incorporate them into the mixture. Microwave for a total of 2 minutes stopping halfway through to make sure it’s not going to explode over your microwave.