01 - Preheat oven to 425°F. Line a baking sheet with parchment paper.
02 - Toss diced sweet potatoes with olive oil, sea salt, and black pepper. Arrange evenly on prepared baking sheet and roast for 25 to 30 minutes, stirring once halfway, until golden and tender.
03 - Place quinoa, water, and salt in a medium saucepan. Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes. Remove from heat and keep covered for 5 minutes. Fluff grains with a fork.
04 - In a food processor, combine fresh basil leaves, pine nuts or walnuts, Parmesan, and garlic. Pulse until finely chopped. With processor running, stream in olive oil and lemon juice until creamy. Season with salt to taste.
05 - Divide fluffy quinoa and mixed greens evenly among four serving bowls. Arrange roasted sweet potatoes, cherry tomatoes, and avocado slices on top. Finish each bowl with a generous spoonful of pesto.
06 - Sprinkle each bowl with lemon zest and pumpkin seeds if desired. Serve immediately.