2 potatoes
2 sweet potatoes
1 red onion, cut into thin strips
1 cup fresh lime juice
1/2 stalk celery, sliced
1/4 cup lightly packed cilantro leaves
1 pinch ground cumin
1 clove garlic, minced
1 habanero pepper, seeded and minced
Salt and freshly ground pepper to taste
1 pound fresh tilapia, cut into 1/2-inch pieces
1 pound medium shrimp – peeled, deveined, and cut into 1/2-inch pieces
1 bibb or Boston lettuce, separated into leaves