Blackened Grouper Po’boys

For the Seasoning:

• 1 tablespoon dried oregano 
• 1 teaspoon onion powder
• 1 teaspoon granulated garlic
• 1 teaspoon paprika
• 1 teaspoon salt
• 1 teaspoon black pepper
• ½ teaspoon cayenne pepper 

For the Lemon Caper Dressing:

• ½ cup mayonnaise 
• 1 tablespoon lemon juice
• ¼ teaspoon mustard powder
• ¼ teaspoon paprika
• ¼ teaspoon cayenne pepper
• 1 tablespoon capers

For the Po’boys:

• 12 ounces grouper (about 2 fillets)
• 2 tablespoons olive oil, divided
• 2 French bread or hoagie rolls
• ½ head iceberg lettuce, shredded
• 1-2 tomatoes, sliced
• Lemon wedges, for serving (optional)