Adobo is a garlic, cumin, and sour-citrus marinade.
Combine first 5 ingredients in a large heavy-duty zip-top plastic bag; add tuna. Seal; chill 1 hour, turning occasionally.
Remove tuna from plastic bag, discard marinade.
Place tuna on a lightly greased rack in a broiler pan.
Broil 4 inches from heat (with electric oven door partially open) 4 minutes or until desired degree of doneness. Do not turn. Serve with Black-Eyed Pea Salad. Garnish, if desired.