Prepare the french toast topping by whisking the egg, milk, brown sugar, and cinnamon in a medium bowl.
Stir in bread cubes and set aside to soak.
For the muffin batter, mix together flour, dry vanilla pudding mix, baking powder, salt, and cinnamon in a large bowl.
Whisk egg and add to dry ingredients along with the milk, brown sugar, and butter. Stir with a wooden spoon until well moistened, batter will be lumpy.
Divide batter evenly among 12 muffin cups lined with cupcake liners.
Top each evenly with french toast topping. Bake at 350 degrees for 25 – 28 minutes. Cool slightly before serving.