Cook the Quinoa: In a medium saucepan, combine the rinsed quinoa, water, and a pinch of salt.
Bring to a boil, then reduce the heat to low, cover, and simmer for 15 minutes, or until all the liquid is absorbed. Fluff with a fork and set aside in a large bowl to cool.
Roast the Asparagus: While the quinoa cooks, preheat your oven to 425°F (220°C). On a baking sheet, toss the asparagus pieces with 1 tablespoon (15 ml / 0.5 fl oz) of olive oil, salt, and pepper.
Spread in a single layer and roast for about 8-10 minutes, until tender-crisp.
Make the Dressing: In a small bowl, whisk together the remaining 3 tablespoons (45 ml / 1.5 fl oz) of olive oil, the fresh lemon juice, and a pinch of salt and pepper.
Assemble the Salad: To the large bowl with the cooled quinoa, add the roasted asparagus, drained white beans, roasted red peppers, sliced celery, and minced scallions.
Pour the lemon dressing over the top.
Toss and Serve: Gently toss all the until everything is well combined and coated in the dressing.
Serve the quinoa mixture over a bed of fresh salad greens and garnish with chopped fresh parsley or basil.
Don't overcrowd the pan when roasting the asparagus. Use two pans if needed to ensure the pieces roast evenly rather than steam.
Let the salad sit for 15-20 minutes before serving to allow the flavors to meld together for an even more delicious result.