Tear the challah into bite-sized pieces and spread them out on a cookie sheet. Leave them out for a few hours to make them slightly stale. Alternatively, toast them in a 350 degree oven for 15 minutes to dry them out.

Soften the bouillon cubes in 1/4 cup of the milk.

In a large bowl, beat the eggs. Whisk in the cream and milk. Fold in the bread cubes so they can absorb the liquid. Fold in the rest of the ingredients. Let the mixture sit in the bowl for an hour, stirring it up every 15 minutes to redistribute the ingredients.

Preheat the oven to 400 degrees.

Spray a 9x13 baking pan with cooking spray and turn the bread mixture into the pan. Bake at 400 degrees for about 50 minutes, until the top is golden and puffy. It will fall after a few minutes out of the oven, but no matter. It will taste just as lofty.