In a very large (60 - 80 quart) pot, half-filled with water, place pot on a jet-style propane burner set on high heat. Add onions, garlic and lemon halves. Bring to a rolling boil over high heat (this can take a while to come to a boil, give yourself about an hour for this step).

Add in the seafood boil seasoning, salt, creole seasoning, bay leaves, and potatoes, bring back to a boil, then reduce heat to medium heat, cooking for about 20 minutes or until potatoes are fork-tender.

Add in the sausage, simmer for 5 minutes.

Add in the mini corn and artichokes (optional) and simmer an additional 10 minutes. 

Add the crawfish, return to high heat, and cook for 5 to 10 minutes. When small gaps appear between the head and tail of the largest crawfish, they're ready. Turn off the heat and let the crawfish rest in the hot liquid for 20 to 30 minutes before serving.

Line a large sheet pan with newspaper or parchment paper. Pour mixture through a large colander basket, or you can use a large spider strainer (slotted spoon) to remove crawfish and vegetables from water. Place crawfish and vegetables on a pan or newspaper lined table. Serve with extra creole seasoning, hot sauce, or remoulade if desired.