To make the remoulade sauce place the mayonnaise, ketchup, spicy mustard, whole grain mustard, garlic clove, paprika, green onion, celery stick, parsley, and paprika into a food processor and blend for a couple of seconds.
Season the remoulade sauce with salt and set aside.
Season the shrimp with Cajun Seasoning.
Grill the shrimp for about 2 minutes on each side over medium-high heat.
While the shrimp cook, brush the bread rolls with butter and grill until nice and toasty.
Spoon about 1-2 Tbsp of remoulade sauce on the bread and then top with the grilled shrimp.