01 - Set the oven temperature to 400°F and line a baking sheet with parchment paper.
02 - Toss the cubed butternut squash with 1 tablespoon olive oil, a pinch of salt, and black pepper. Arrange in a single layer on the baking sheet and roast for 25 to 30 minutes, turning halfway through, until tender and golden brown.
03 - In a medium saucepan, combine quinoa with 2 cups water. Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes or until water is absorbed. Remove from heat and fluff with a fork; allow to cool slightly.
04 - Whisk together the remaining 2 tablespoons olive oil, apple cider vinegar, maple syrup or honey, Dijon mustard, minced garlic, sea salt, and black pepper in a small bowl.
05 - In a large bowl, mix the cooked quinoa, roasted squash, sliced red onion, and fresh greens. Drizzle the dressing over the mixture and toss gently to combine.
06 - Top the salad with toasted pumpkin seeds and crumbled feta cheese if desired. Serve warm or at room temperature.