Preheat your oven to 350°F if you opt to bake the crab cakes.
Sauté vegetables: In a pan, heat butter and olive oil. Add the bell peppers and celery, cooking until soft.
Mix: In a separate bowl, combine crab meat, breadcrumbs, mayonnaise, mustard, and eggs.
Combine: Stir in the sautéed veggies, add parsley, and season with salt, pepper, and optional crab boil seasoning.
Chill: Cover the mixture and refrigerate for 30 minutes; it helps the cakes hold their shape.
Shape: Form the mixture into cakes using your hands.
Cook: Fry in a pan over medium heat with olive oil, or bake until crispy and golden brown.