- 1/4 cup (1/2 stick) unsalted butter, plus more for dish
- 2 cups chopped greens, such as kale or swiss chard
- 1 cup orzo pasta or Israeli (large pearl) couscous
- 2 large heads cauliflower (about 2 pounds), cut into florets
- 1/4 cup all-purpose flour
- 3 cups milk
- 2 tablespoons finely chopped fresh marjoram or oregano
- 1 teaspoon coarse salt
- 1/4 teaspoon freshly ground black pepper
- 1/8 teaspoon cayenne pepper
- 3 cups finely grated (about 10 ounces) Gruyere cheese
- 1/4 cup fresh breadcrumbs
- 1/4 cup coarsely grated (about 2 ounces) Parmesan cheese
- Preheat oven to 400 degrees with rack in lower third. Butter a 1 1/2-quart, deep, wide ovenproof dish. Put greens in bottom of dish. Arrange pasta or couscous over greens. Top with cauliflower.
- Melt butter in a medium saucepan over medium heat. Whisk in flour. Reduce heat to medium-low. Cook, stirring, 2 minutes. Whisk in milk; cook, whisking, until mixture thickens, about 4 minutes. Remove from heat. Whisk in marjoram, salt, black pepper, and cayenne. Whisk in Gruyere until smooth. Pour over cauliflower. Sprinkle with breadcrumbs. Set dish on a baking sheet.
- Bake 30 minutes. Sprinkle with Parmesan. Reduce temperature to 350 degrees; bake until cauliflower is tender, about 40 minutes. (If browning too quickly, tent with foil.) Transfer to a wire rack; let cool 10 minutes before serving.