Grate cheese into large bowl using small side of grater. Drain pimentos and add to cheese. Sprinkle the cayenne (start with ¼ or ½ teaspoon and taste after mixing) and black pepper over the cheese. Stir in 1 cup of mayonnaise. You may decide to add an additional ¼ cup depending on how creamy you like it. Mix well and taste. Add more mayo, cayenne, and a little salt if needed.