Make four-day preserved lemon zest: Scrub lemons and with a vegetable peeler remove zest in strips. In a saucepan of boiling water blanch zest 1 minute and drain in a sieve. Transfer zest to a glass jar (about 1-cup capacity). Add salt and juice, pressing zest down to keep it covered by lemon juice, and cover jar with a tight-fitting glass lid or plastic-coated lid. Let zest stand at room temperature 4 days, shaking jar each day. Preserved lemon zest keeps, covered and chilled, 6 months. Makes about 1/2 cup.

make the veal: Preheat oven to 275°F.

In a heavy kettle large enough to hold veal shanks in one layer without crowding arrange shanks and season with salt and pepper. Roast shanks in middle of oven, covered tightly, 3 hours, or until tender. (Meat will give off juices as it cooks.)

While shanks are roasting, in a large saucepan combine chick-peas with enough water to cover by 4 inches and simmer, covered partially, 1 1/2 to 2 hours, or until tender but not falling apart. Drain chick-peas in a colander. Chick-peas may be cooked 2 days ahead, cooled, uncovered, and chilled, covered.

Transfer shanks to a deep platter and keep warm, reserving pan juices.

In a large heavy skillet heat oil over moderate heat until hot but not smoking and cook onion, stirring, until softened. Add artichoke hearts, chick-peas, and reserved pan juices and simmer, covered, until artichoke hearts are just tender, about 3 minutes. Transfer about 1/2 cup chick-peas with a slotted spoon and about 1 cup pan juices from skillet to a blender and purée. Stir purée into artichoke and chick-pea mixture to thicken and stir in coriander and salt and pepper to taste.

Spoon artichoke and chick-pea mixture over shanks and sprinkle with preserved lemon.