Arugula-Asparagus Salad

In a small bowl combine onion and vinegar. Press down on the onion so as much of it is covered by the vinegar as possible. Cover with foil and let stand at room temperature for at least 30 minutes or in the refrigerator for up to 24 hours, stirring occasionally.

Cook asparagus, covered, in enough boiling water to cover for 2 to 3 minutes or until crisp-tender. Drain and rinse asparagus with cold water to cool quickly. Drain well. In a large bowl combine drained asparagus, arugula, and mint.

Using a slotted spoon, transfer onions to the asparagus mixture. Pour 3 tablespoons of the vinegar from the onion bowl into a small screw-top jar. Add oil, salt, and pepper. Cover and shake well. Drizzle over asparagus mixture; toss gently to coat. Serve immediately by dividing among four serving plates.