Combine vinegar with 1 quart of water in a large bowl. Trim stems almost flush with artichoke bottoms so they sit fla Tbsp Slice off the top ¼ of the artichoke and cut tips of leaves with a sharp paring knife or kitchen shears. Periodically rub cut ends with acidulated water to prevent discoloration. Trim outer leaves from artichokes and cut into quarters. Remove and discard fuzzy centers.
In a large saucepan, combine artichokes, chicken broth, water, shallot, lemon juice, thyme, salt and pepper. Bring to a boil. Cover, reduce heat and simmer for 30 minutes, or until artichokes are tender. Drain artichokes, reserving liquid. Scrape flesh from leaves; reserve. Cut artichoke hearts into pieces. Combine strained cooking liquid, artichoke flesh, artichoke hearts and half-and-half in a blender. Process until smooth. Taste for seasonings. Serve warm or chilled.Servings: 4