Grilled Pimento Cheese Sandwiches

Name: Grilled Pimento Cheese Sandwiches
Ingredients: 8 ounces sharp white cheddar cheese, coarsely grated (about 2 loosely packed cups); 1 red bell pepper--roasted, peeled, seeded (or jarred) and finely diced; ¼ cup mayonnaise (preferably homemade or duke's brand); ¾ teaspoon smoked sweet spanish paprika; ½ teaspoon dijon mustard; ¼ teaspoon kosher salt; Pinch of cayenne pepper; 8 slices soft white bread; 4 tablespoons (½ stick) unsalted butter, divided; 4 pickled okra spears, for garnish (optional)