Rinse quinoa under cool water and combine with water in a saucepan. Bring to a boil, reduce to low, cover, and cook for 15 minutes. Let it cool in a bowl.

In a jar, whisk together lime juice, olive oil, maple syrup, Dijon mustard, salt, and pepper. Shake well until emulsified.

In a large bowl, combine cooled quinoa, chopped strawberries, avocado, toasted walnuts, feta cheese, and arugula. Mix carefully.

Pour dressing over the salad and gently toss to combine, making sure not to bruise the avocado and strawberries. Serve immediately.