- Bring water to a boil in a large skillet over medium heat.
- Add catfish fillets and return to a boil.
- Reduce the heat to medium-low, cover, and gently simmer for 5 to 7 minutes or until flakes easily when tested with a fork.
- Using a slotted spatula, remove fillets from water and place on a plate to cool slightly.
- Cut into bite-size pieces.
- Cut artichoke hearts in half.
- Place artichoke hearts, cheese, and zucchini in a large plastic bag and shake to mix.
- Add catfish pieces.
- Mix vinegar, olive oil, green onions, garlic, sugar, basil and pepper in a small bowl.
- Pour over catfish mixture in bag.
- Seal bag tightly and refrigerate for 6 hours or overnight, turning bag occasionally.
- To serve, let marinated catfish mixture stand at room temperature for about 15 minutes.
- Drain and arrange on a lettuce-lined serving platter.
- Serve with toothpicks.