Melt butter in a large skillet over medium heat.
Add diced celery, onion, and bell pepper. Sauté until the vegetables are tender.
Stir in Creole seasoning, seafood seasoning, and minced garlic. Cook for another minute until fragrant.
Sprinkle in the flour, stirring constantly to coat the vegetables and form a roux.
Cook for about 2 minutes, until the roux begins to lightly brown.
Slowly add crawfish stock (or substitute), stirring constantly until the mixture thickens.
Stir in crawfish tail meat, then add heavy cream. Reduce heat to low and let simmer for 15 minutes.
Remove from heat, stir in fresh lemon juice, and allow to cool to room temperature.
Once cooled, mix in the cooked rice. Set aside.