Rinse the quinoa under cool water, then combine with 3 cups of water and 1/2 teaspoon salt in a medium saucepan. Bring to a boil, then turn down the heat to medium-low, cover, and cook until the quinoa is fluffy and chewy, about 15-20 minutes.
Place the butternut squash, onion and garlic in a sheet pan, then toss with olive oil and maple syrup. Sprinkle with salt and pepper. Toss everything together. Roast in the oven until the squash is tender - about 15 to 20 minutes.
Lightly toast the pecans in a small pan until fragrant, set aside to cool.
Combine the quinoa and butternut squash mixture in a large bowl and allow to cool almost to room temperature. The quinoa should feel just barely warm to the touch. You can speed up this process by spreading the quinoa and butternut squash mixture into a thin layer on a large sheet pan and placing in the fridge for 20-25 minutes.
Once the quinoa mixture has cooled, add pecans, parsley, pomegranate seeds, and scallions and toss to combine.
Mix the sauce ingredients together then add to the bowl and toss well to combine.