Heat the oil in a skillet over medium-high heat and sautÈ the andouille for 3 to 4 minutes. Add the onions and celery. Cook, stirring often, for 4 to 5 minutes, or until slightly wilted. Add the garlic and cook for 1 minute. Remove from the heat and set aside.
Combine the eggs, cream, milk, salt, cayenne, and black pepper and mix well. Add the bread, the andouille mixture, and half of the cheese. Fold to mix thoroughly. Cover and refrigerate for 30 minutes.
Preheat the oven to 375?F.
Transfer the mixture to a 2 1/2- to 3-quart baking dish. Sprinkle with the remaining cheese. Bake for 45 minutes, or until golden brown on top.
Remove from the oven and let stand for 5 minutes.
Serve warm directly from the baking dish.
Yield: 8 to 10 servings