Salmon Wrapped Poached Eggs

Name: Salmon Wrapped Poached Eggs
Ingredients: 1/2cup sour cream; 2 teaspoons fresh lemon juice; 1/4 cup olive oil; 1 tablespoon finely chopped fresh chives; 1/2 tablespoon chopped fresh tarragon; 1/2 teaspoon kosher salt; 1 small red onion, thinly sliced; 2 ripe California avocados; 1 to 2 tablespoons fresh lemon juice; 6 individual brioches, each cut horizontally into 3 (1/2-inch-thick) rounds and lightly toasted; 1/4 lb sorrel or arugula, coarse stems discarded; 4 teaspoons distilled white vinegar; 16 large eggs; 1 lb thinly sliced smoked salmon; Garnish: chopped fresh chives