Preheat oven to 350 degrees.
Add chopped donuts into a large bowl.
In a separate bowl whisk together eggs, milk, condensed milk, vanilla, and cinnamon.
Pour on top of the donuts and mix to coat well.
If you are adding raisins sprinkle them on and mix in.
Let sit and soak for 10 minutes.
Coat a 9x9 baking dish with non stick spray.
Pour the donuts and custard in the dish and spread out evenly.
Bake for 45 minutes until golden and cooked through.
Slice into squares, top with whipped cream if you'd like, and serve warm.
Store leftovers in the fridge in a covered container for up to 5 days.