- Using a bread knife, slice off top of artichokes. Remove tough outer leaves. Using a vegetable peeler or paring knife, peel sides and base of each artichoke. Cut each artichoke into quarters and remove any prickly tips that may have formed. Soak in 1 quart of water with the juice of 2 lemons. Drain artichokes and cut each quarter in half to form wedges.
- In a medium saucepot heat 4 tablespoons olive oil. Add onion, celery, drained artichokes, capers, and olives. Toss to get some color.
- Add remaining olive oil, tomato paste, and anchovies and let bubble rapidly. Then reduce heat and simmer 30 minutes. During last 5 minutes, add diced tomatoes, red wine vinegar, chili flakes, and sugar. Remove from heat and let cool.
- Place a large sauté pan over high heat. Heat vegetable oil and add grouper fillets. Sear on high for about 2 minutes or until you gently move pan and the fish moves as well. Flip each fillet and reduce heat to medium-low and continue cooking fish for about 5−6 minutes or until the fish is easily pierced with the tip of a paring knife.
- Place artichoke caponata on top of each fish and enjoy.