Instructions

1. Preheat the oven to 450°F. Oil a heavy nonstick 16-by-10-inch baking sheet with olive oil.
2. To make the sauce: In a small heavy saucepan, melt the butter over medium heat. Add the flour and cook for 1 minute, stirring constantly. Gradually whisk in the milk and add the nutmeg. Whisk over medium heat until the mixture thickens to sauce consistency and is smooth, about 6 minutes. Stir in the salt and pepper.
3. To make the pizza: Using your fingers, stretch the dough onto the prepared baking sheet in a large rectangle. Spoon the sauce on top and spread evenly, leaving a 1-inch border around the edge of the dough. Sprinkle with the mozzarella cheese. Toss the pot roast with some of its pan juices to moisten and arrange on the dough. Sprinkle with Parmesan cheese.
4. 4 Bake the pizza for 15 minutes. Remove the baking sheet from the oven and top the pizza evenly with the kale. Drizzle with olive oil and sprinkle with salt. Bake for 8 minutes longer, until the kale is crispy. Remove from the oven, cut into squares, and serve.