Sweet Potato Gratin with Vanilla Bean and Bay Leaves

For many families, Thanksgiving isn’t complete without a sweet potato casserole, that sticky-sweet concoction more appropriate for the dessert table than the main event. It’s a classic for good reason, though we felt the gooey marshmallows had to go. We started by roasting the sweet potatoes, a simple, hands-off process that can be done a day ahead. Roasting rather than boiling produces cleaner, deeper flavors and a better, less watery texture. In lieu of marshmallows we infuse cream with vanilla bean and bay leaves and add a dusting of black pepper for an overall effect that hints at marshmallow but is far more nuanced, compelling and aromatic. A crunchy topping of dark brown and white sugar with a touch of cayenne keeps the dish adults table-appropriate. We found that using a mesh strainer to sift the sugar over the potatoes produced even browning and an attractive crust. But strainers with very fine mesh tended to clog. If yours does this, just sprinkle the sugar by hand, smoothing it into an even layer with your palm.