Buffalo Chicken Grilled Cheese Sandwich

1/4 cup cooked shredded chicken, warm
1 tablespoon hot sauce
1/2 tablespoon mayonnaise (optional)
1 tablespoon carrot, grated
1 tablespoon celery, sliced
1 tablespoon green or red onion, sliced or diced
1 tablespoon blue cheese, room temperature, crumbled
1/4 cup cheddar cheese, room temperature, grated
1 tablespoon butter or margarine

Mix the chicken, hot sauce, mayonnaise, carrot, celery and onion in a small bowl.

Assemble sandwich and grill until golden brown and the cheese has melted, about 2-3 minutes per side.