Combine tuna, mayo, green onion, capers,
sriracha, salt/pepper, and mozzarella in a
Toast both sides of bread with butter using a
broiler until golden brown.
Add tuna mixture to each bread slice, coating
the entire surface. Top with sharp white
cheddar. Dust with cayenne.
Broil for 5-6 minutes until cheese is melted
and golden. Serve with sliced dill pickles.