Kale and Leek Gratin

Preheat oven to 375°F (190°C). Grease a 9x13 inch baking dish.

Heat 2 tablespoons olive oil in a large skillet over medium heat. Add leeks and cook until softened, about 8-10 minutes, stirring occasionally. Add garlic and cook for another minute until fragrant.

Add chopped kale to the skillet and cook until wilted and tender, about 5-7 minutes, stirring occasionally. Season with salt and pepper.

In a separate saucepan, melt butter over medium heat. Whisk in flour and cook for 1-2 minutes, stirring constantly to form a roux.

Gradually whisk in milk until smooth. Bring to a simmer, stirring constantly. Reduce heat and simmer for 5 minutes, stirring occasionally, until sauce has thickened.

Remove from heat and stir in Gruyere cheese, nutmeg, salt, and pepper. Taste and adjust seasonings as needed.

Add the kale and leek mixture to the cheese sauce and stir to combine.

Pour the mixture into the prepared baking dish.

In a small bowl, combine breadcrumbs, Parmesan cheese, and 1 tablespoon olive oil. Sprinkle evenly over the gratin.

Bake for 25-30 minutes, or until golden brown and bubbly.

Let cool for a few minutes before serving.