This cauliflower carrot gratin recipe will be your new favorite side dish, but it is really reminiscent of vintage recipes of the past. This vegetable dish goes with so many different main courses; roasted chicken, fish, turkey, or steak. Try this twist on a traditional potato au gratin. This cheesy gratin with a buttery bread crumb topping is a perfect holiday side dish – but so simple to put together, you can make it any time!