Cold toppings included spicy broccoli, pickled pink onion, and red cabbage.Grace Dean/Business InsiderI visited rival salad chains Cava and Sweetgreen to get build-your-own bowls.Both restaurants offered an extensive choice of bases, vegetables, sauces, and toppings.But Sweetgreen charged extra for many of its tastiest add-ons.Salad-bowl chain Cava has ambitious expansion plans.