Fill a large 5-gallon pot half-full with water.
Add the garlic, bay leaves, lemons, and seasoning into the pot. Bring it to a boil over high heat, then reduce to a simmer for about 20 minutes.
Stir in the onions, potatoes, baby corn, and green beans and look for another 15 minutes. Vegetables are optional, so you don't have to add it if you don't want to.
Add the crawfish and increase the stove’s heat. Cook them for about 5 minutes until shells turn bright red. If the tail pulls out easily, this means they’re done. Be careful not to overcook the crawfish as they might become tough if you do.
Drain the water from the pot. You can either serve your dish hot with steaming vegetables on the side or leave the crawfish in the pot to soak in the hot water for 20 to 30 minutes. The longer they soak, the more flavour they'll have.