1. Preheat oven to 350°F. Grease or butter an 8x8 baking dish.
2. Cut donuts into chunks and place in a large bowl.
3. Whisk half and half, sugar, eggs, vanilla and cinnamon in a small bowl. Pour over the donuts and let liquid absorb. Gently stir mixture to ensure all donuts are coated. About 10 minutes.
4. Cook for 30-40 minutes until golden.