Crab Louie Salad

• 1 lb crab meat , in large chunks
• Juice of a lemon , freshly squeezed
• black pepper , freshly ground
• 3 hearts romaine lettuce
• 4 tablespoons chopped fresh chives
• 4 hard-boiled eggs , sliced
• 2 medium tomatoes , cut into thin wedges
• 2 stalks celery , sliced
• 1 red onion , sliced
• 1 English cucumber , peeled and sliced
• 4 Lemon wedges
• 12 asparagus spears , trimmed and steamed
• 1 avocado , sliced

For the sauce

• 4 tablespoons ketchup
• 1 teaspoon Dijon mustard
• 1 teaspoon Worcestershire sauce 
• 2 teaspoons horseradish
• 4 tablespoons red wine vinegar
• 3 tablespoons mayonnaise
• 4 tablespoons vegetable oil
• 2 tablespoons very finely chopped scallion
• 1 garlic clove , finely chopped
• black pepper , freshly ground
• black peppercorns