This is Jazz Fest food at its best. There are plenty of crawfish bread recipes out there, with all kinds of crazy ingredients, but this one is my favorite, because it's simple, delicious, and the closest I have found to the famous Fest dish. You can use thawed frozen crawfish tails. But check the packaging, and make sure they came from Louisiana. If you buy them from anywhere else, they won't be as good, and Louisiana crawfish farmers will come and haunt your dreams until you go mad.
- Slice French bread in half lengthwise and scoop out the inside of the loaf. Set aside. In a large skillet, melt butter over medium-high heat. Sauté crawfish, onions, celery, bell peppers and garlic 15 minutes. Blend in dry mustard and mayonnaise. Add cheeses and blend until melted. Spread crawfish mixture inside the bread then put halves back together. Butter the top of the loaf, wrap it in foil and bake on a barbecue pit or in a 350°F oven for 20–30 minutes. Cut bread into slices and serve hot.