This salad packs a mouthful of vibrant colors and flavors, all in one bite. Hearty kale holds up to robust mix-ins (pomegranate seeds, pistachios, cooked quinoa) and keeps its crispness after soaking in vinaigrette, which Amanda Haas suggests you do, both for flavor and meal prep ease.
Julienne the kale leaves: Grasp the bottom of the stem with one hand, and use the other to firmly strip the leaf from the stem on either side; discard the stem. Repeat with all the leaves. Stack the leaves, roll them like a cigar, and coarsely chop crosswise to create ribbons of kale. Place in a large bowl and set aside.
Vinaigrette: In a small bowl, whisk together mustard, vinegar, and honey. Season to taste with salt and pepper. Slowly add the olive oil in a steady stream, whisking continuously. At least 30 minutes before serving, combine the kale with half of the vinaigrette; use your hands to toss, making sure each leaf is coated. Letting the leaves rest in the vinaigrette eliminates the need for massaging. Set aside.
Just before serving, slice thin half-moons of red onion; separate the slices with your fingers, and sprinkle on the salad. Add the pistachios, pomegranate seeds, and cooked quinoa. Top with some or all of the remaining vinaigrette as needed, then toss well with your hands to combine. Transfer to serving plate, making sure the ingredients are evenly distributed, and serve immediately.