Preparation Preheat oven to 450°F with rack in middle. Toss asparagus with oil and 1/4 teaspoon each of salt and pepper in a 4-sided sheet pan. Roast until just tender, about 10 minutes. Mash together butter, horseradish, and 1/8 teaspoon salt. Toss asparagus with horseradish butter.
Preparation Preheat oven to 450°F with rack in middle. Toss asparagus with oil and 1/4 teaspoon each of salt and pepper in a 4-sided sheet pan. Roast until just tender, about 10 minutes. Mash together butter, horseradish, and 1/8 teaspoon salt. Toss asparagus with horseradish butter.