Prepare quinoa by rinsing thoroughly with cool water in a fine-mesh strainer. Then add to a small saucepan with vegetable stock (or water) and bring to a boil over high heat.
Once boiling, reduce heat to low, cover, and simmer for 15-20 minutes, or until liquid is absorbed and quinoa is fluffy like rice. Remove from heat and set aside to cool slightly.
In the meantime, prepare dressing by heating a small skillet over medium heat. Once hot, add 1 Tbsp. grape seed oil and minced shallot; sauté until tender and slightly caramelized, about 5 minutes, stirring often. Remove from heat to cool.
Add shallot to a food processor or blender with balsamic vinegar, olive oil, maple syrup, and a pinch each of salt and pepper. Blend until pureed, scraping down sides as needed. Taste and adjust seasonings as needed.
To plate, top the mixed greens with slightly cooled quinoa, blueberries, raspberries and walnuts. Serve with dressing. Best when fresh. Serves 2 as an entrée, or 4 as a side dish.