Sprinkle the gelatin over the water and ¼ cup beef broth in the blender and allow to stand. Heat the remaining beef broth to boil and add to the blender, whirling until all the gelatin is dissolved. Add the salt, lemon juice, and salad dressing and blend well. Stop, add the onion, then the spinach and eggs until eggs are just coarsely chopped. Stir in the bacon and turn into a ring mold or 6-cup mold. Chill for 2-3 hours or until firm. Unmold, garnish with pimiento strips and fill with the desired mixture.