1. Preheat oven to 350F.
2. Cut the challah into small dice and place in a butter 3-quart casserole dish.
3. Warm half and half, 1/2 of the sugar and cinnamon. In a bowl combine the remaining sugar, vanilla and eggs whip until well pale in color.
4. Slowly pour the warm half and half into the egg mixture stirring constantly so the eggs don’t cook.
5. Pour the custard mixture over the bread in the baking dish make sure it's coated. Let the pudding sit for 25 minutes, so the bread can fully absorb the custard.
6. Bake 40 minutes or until puffy and set.
7. Remove, and let stand 10 minutes before serving.