Purge the crawfish by placing live crawfish in a large cooler and cover with cool water and a generous amount of salt. Let them soak for 15 to 20 minutes, stirring occasionally to encourage them to expel mud and grit. Drain and rinse thoroughly, discarding any dead crawfish that float or do not move.

Set up your propane burner outdoors on a stable, level surface away from any structures. Fill your large pot with water to about two thirds full, approximately 8 to 10 gallons.

Bring the water to a rolling boil over high heat. Add the crawfish boil seasoning, salt, cayenne pepper, liquid crab boil, bay leaves, and halved lemons, squeezing the juice into the pot before dropping them in. Let this seasoned water boil for 10 minutes to fully bloom the spices.

Add the garlic heads, onions, and celery to the boiling water. After 5 minutes, add the potatoes and let them cook for 10 minutes.

Drop in the corn cob halves and andouille sausage pieces. Cook for about 10 minutes to absorb the spicy broth.

Carefully lower the basket of purged crawfish into the boiling water. Crank the heat to bring it back to a boil as quickly as possible. Once boiling resumes, cook for exactly 3 to 5 minutes.

Turn off the burner completely and add the entire pound of butter to the pot. Let everything sit in the hot liquid for 20 to 30 minutes, stirring occasionally. Taste a crawfish at 20 minutes and continue soaking if you want more intense flavor and heat.

Lift the basket to drain, letting excess liquid fall back into the pot. Dump everything onto a newspaper covered table and serve immediately while hot.