Authentic Louisiana Crawfish Pie

Ingredients

• 1 stick butter
• 2 stalks celery
• 2 Tbsps garlic
• 1 lb crawfish tails
• 1 onion
• 1 bell pepper
• 1 Tbsp fresh parsley
• 1/2 tsps cayenne pepper
• 1/2 tsps white pepper
• 1/2 tsps black pepper
• 1/2 tsps paprika
• 1/2 tsps garlic powder
• 1 tsp oregano
• 2 frozen " pie shells
• 1 Tbsp flour
• 1 1/2 cups half and half
• 1/3 stick butter
• 2 cups mild cheddar cheese