Directions

• Step 1 Preheat oven to 425 degrees F. Prepare your breadcrumbs in a food processor. You want a coarse (rather than fine) grind. Toss the crumbs with oil and salt and pepper and then spread onto a rimmed baking sheet. Bake for about 5 minutes until the crumbs begin to crisp and brown. Remove from oven and set aside.
• Step 2 Raise oven temperature to 475 degrees F.
• Step 3 Bring a large pot of water to a boil. Prep your asparagus and drop it into the boiling water. Cook until the asparagus is crisp tender. Remove from pot and set aside.
• Step 4 Drop the peeled and sliced potatoes into the boiling water you used for the asparagus. Boil the potato slices for about 10 minutes until the slices are tender but still hold their shape. Drain. Arrange the potato slices on the bottom of a 2-quart baking dish that measures about 8 1/2 inches by 11 1/2 inches. The dish should be at least 1 1/2 inches deep.
• Step 5 Melt butter in a saucepan over medium heat. Add flour and cook until the flour gets a nutty aroma. This will happen quickly and takes only about 30 seconds. Use a whisk to slowly whisk the milk into the cooked flour. Whisk until there are no lumps and until the mixture thickens slightly. This will take 1 to 2 minutes. Remove the pan from the heat and whisk in the two cheeses until the cheeses are melted and you have a smooth sauce. Season sauce with salt and pepper to taste.
• Step 6 Pour one half of the cheese sauce over the sliced potatoes you’ve arranged in the baking dish. Top with one half of the asparagus. Pour the rest of the cheese sauce over the potatoes and asparagus. Arrange the remaining asparagus on top and sprinkle with the toasted bread crumbs.
• Step 7 Bake for 10 to 12 minutes. You want to see the sauce bubbling around the edges of your gratin. Remove from the oven and let cool for a few minutes before serving.
• Step 8 Garnish with chopped chives if desired.