I first discovered this dish when I was preparing for a friend’s Thanksgiving dinner. I’d been told to bring a potato dish, and I wanted to bring something special. I stumbled onto a version of root vegetable gratin on Smitten Kitchen and was inspired to create my own variation. It turned out great --- tasty and unique, indulgent, but nutritious. Now I make it regularly for dinner alongside a simple roast chicken breast.
The blend of starchy vegetables here adds color and texture to the classic potatoes au gratin. I’ve cut out alliums except for garlic because they tend to overpower the delicate vegetal flavors. Pecorino Romano’s strong, salty taste is the perfect counterpoint for the vegetables’ sweetness.
Pro tip: This gratin has creamy but relatively thin sauce. If you prefer a thicker coating, replace 1/2 cup of the cream with full-fat sour cream.