01 - Set oven to 425°F and line a baking sheet with parchment paper.
02 - Toss sweet potato cubes with olive oil, salt, and pepper. Spread evenly on baking sheet and roast for 25 to 30 minutes, stirring halfway, until golden and tender.
03 - Bring quinoa, water, and salt to a boil in a saucepan. Cover, reduce heat to low, and simmer for 15 minutes. Remove from heat and let stand 5 minutes, then fluff with a fork.
04 - Whisk tahini, lemon juice, water, olive oil, maple syrup or honey, minced garlic, salt, and pepper in a bowl until smooth. Add additional water for thinner consistency if needed.
05 - Divide greens among four bowls. Add a serving of quinoa, roasted sweet potato cubes, cherry tomatoes, red onion, and avocado slices to each.
06 - Drizzle with lemon-tahini dressing and garnish with feta, seeds, and fresh herbs as desired. Serve immediately.