5 lb. shrimp, peeled and cooked
10 white onions, sliced
2 c. olive oil
1 1/2 c. cider vinegar
3 1/2 oz. jar capers, with juice
Salt, sugar, hot pepper sauce and Worcestershire sauce to taste
Optional: 2 cans artichoke hearts and - or 1 1/2 lb. fresh button mushrooms

Layer shrimp and onions in a deep casserole. Combine remaining ingredients to make dressing. Pour dressing over shrimp and onions. Cover and chill 12 hours before serving. Stir occasionally. Lift out of dressing and arrange on large platter.