For the vinaigrette: Place all ingredients except oil in a food processor with metal blade. With machine running slowing drizzle in the oil until emulsified.
For the salad: Peel and devein shrimp and cook in boiling water seasoned with Old Bay for two minutes. Drain in colander and pour a big glass of ice cubes on top of the shrimp to stop cooking. Chill for one hour. Fill a large saucepan with water and 1 tablespoon salt. Bring water to a boil Separate 1 medium head of broccoli into smaller flowerettes. Place in boiling water and cook for two minutes. Drain in a colander and pour a generous glass full of ice over broccoli to stop cooking. After about 15 minutes, dig through the broccoli and remove any remaining ice cubes.
To serve, place big leaves of bibb lettuce on two plates. Sprinkle with shrimp and broccoli and divide avocado and mound in the middle of each salad. Drizzle with bacon jam vinaigrette.