Salmon burgers with a zesty lemon dill spread

Ingredients

• 1 1/2 pounds fresh salmon, skin removed
• 1/4 cup mayonnaise
• 3 tablespoons Dijon mustard
• 1/4 teaspoon cayenne pepper
• 1/2 teaspoon garlic powder
• 1/4 teaspoon ground black pepper
• 1 teaspoon lemon zest
• 1/4 cup red onion, chopped
• 1 teaspoon fresh dill, chopped
• 1/4 teaspoon kosher salt
• 1/2 cup plain breadcrumbs
• 6 burger buns
• 1 cup mayonnaise
• 2 tablespoons lemon juice
• 1 tablespoon fresh dill, chopped
• 2 teaspoons fresh parsley, chopped
• 1/2 teaspoon Old Bay seasoning
• 1 garlic clove, minced
• Salt
• pepper