In a small bowl or medium jar, combine the lemon juice, olive oil, mustard, and garlic. Whisk to combine or shake with the jar lid on tight. Season with salt and pepper, to taste, and set aside.
Add water, quinoa, and salt to a medium saucepan and bring to a boil over medium heat. Boil for 5 minutes. Turn the heat to low and simmer for about 15 minutes, or until water is absorbed. Remove from heat and fluff with a fork.
While the quinoa is cooking, cook the asparagus. In a large skillet, heat the olive oil over medium heat. Add the asparagus and fresh lemon juice. Cook until tender, about 5 minutes.
In a large bowl, combine quinoa, asparagus, chickpeas, green onion, and feta cheese. Pour the dressing over the salad and stir until well coated. Season with salt and pepper, to taste. Serve.
Notes
If you need the salad to be vegan, you can omit the feta cheese and add nutritional yeast.