1. In a large pot, combine potatoes, onions, garlic, 1 tablespoon salt, and 10 cups water. Wrap mint and tarragon sprigs and bay leaf in cheesecloth and tie with kitchen twine; add to pot. Bring to a boil, then reduce heat to low and cook, partially covered, until potatoes are just tender, about 12 minutes. Add asparagus, chickpeas, and snap peas; simmer until tender, about 10 minutes. Lightly crush potatoes and garlic.

2. Stir in asparagus tips, lettuce, and 1 cup greens until greens are just wilted. Season with salt and pepper. In a bowl, toss herb leaves with remaining 2 cups greens. Serve soup, topped with a small mound of herb mixture and a drizzle of oil.