This comforting baked keto dish could, if you squint your eyes hard enough, pass for baked pasta, swimming in cream and topped with nutty, browned Gruyère cheese. Already have your own favorite homemade or frozen store-bought meatball recipe? Use it here in place of the from-scratch meatballs; just make sure they’re the same size and are thawed completely.
Mustardy Meatball and Cauliflower Gratin with Gruyère
Heat the oven to 450 degrees. Place four 2-cup gratin dishes on a foil-lined baking sheet.
Bring 1 cup water to a simmer in a large skillet over medium heat. Add the cauliflower, season with salt and cover the skillet. Cook until the cauliflower florets are just tender enough to be pierced with the tip of a knife, about 2 minutes. Uncover and continue cooking until the water evaporates and the cauliflower is fully tender, 4 to 5 minutes more. Divide the cauliflower among the prepared gratin dishes.
In a medium bowl, break apart the ground beef with your fingers into pieces about the size of a dime. Dollop the mustard over the beef then season liberally with salt and pepper. Use your fingers to gently toss the beef until it’s well-coated with the seasonings. Roll walnut-size pieces of beef into about 32 balls (1¼-inch-diameter) and divide them among the gratin dishes, resting them on the cauliflower.
Pour ½ cup cream over the meatballs and cauliflower in each dish, season with salt and pepper, then top each with ¾ cup grated cheese. Bake until the meatballs are cooked through and the cheese is golden brown and bubbling on top, about 30 minutes. Serve while warm.