Heavy cream infused with fragrant garlic, rosemary, bay leaves, and a dash of white pepper transforms often-overlooked turnips into a bubbly and decadent dish that’s layered with nutty Gruyère and sharp pecorino Romano cheeses. Think of this dish as an earthy alternative to a traditional potato gratin or scalloped potatoes, where the root vegetable adds a little sweetness and a firmer texture than potatoes. It’s still very rich, creamy, and cheesy, so it’ll feel right at home on the holiday table.