1
["Preheat the oven to 400u00b0F.", "Line a large baking sheet with parchment paper. Set aside.", "Spray a 9-inch square baking dish with cooking spray. Set aside.", "Chop the cauliflower into 1-inch florets. Arrange the florets onto the lined baking sheet. Drizzle with olive oil and season with salt and black pepper, to taste. Stir with rubber spatula to distribute the oil.", "Roast the cauliflower for 10 minutes, until the oil is sizzling and the outsides of the florets are slightly softened.", "Remove the baking sheet from the oven. Reduce the oven temperature to 375u00b0F.", "Finely mince the garlic.", "In a large pot over medium heat, melt the butter. Add the garlic and saute for 30 seconds, until fragrant. Sprinkle the flour into the pot. Whisk to thoroughly combine. Continue whisking for 1-2 minutes, until the roux turns slightly golden and begins to smell toasty.", "Slowly stream the milk into the pot while continuing to whisk. Cook the mixture, whisking steadily for 4-5 minutes, until it begins to thicken and bubble.", "Once bubbling, turn off the heat. Add shredded cheddar, Gruyere cheese, salt, and black pepper to the pot. Whisk slowly until the cheeses are fully melted and the sauce is smooth.", "Once the sauce is smooth, add the roasted cauliflower to the pot. Stir until the florets are thoroughly coated.
2
Pour the contents of the pot into the greased baking dish.", "Place the bread crumbs, Parmesan, cheddar cheese, salt, and black pepper in a medium mixing bowl. Mix with a fork to combine. Add melted butter to the bowl, and stir until all the breadcrumbs are moistened. Sprinkle the crumbs in an even layer over the cauliflower.", "Bake the gratin for 18-22 minutes on the middle rack of oven, until the edges are bubbling and the top is golden-brown.
