01 - Rinse quinoa or rice thoroughly. In a medium saucepan, combine grains with water or vegetable broth. Bring to a boil over high heat, then reduce heat to low, cover, and simmer for 15-20 minutes for quinoa or 35-40 minutes for brown rice. Cook until grains are tender and liquid is fully absorbed. Remove from heat, fluff with a fork, and let cool for 5 minutes.
02 - In a small mixing bowl, combine tahini, fresh lemon juice, extra-virgin olive oil, minced garlic, water, salt, and black pepper. Whisk vigorously until the mixture is smooth and creamy. If the dressing is too thick, gradually add more water, 1 teaspoon at a time, until desired consistency is reached.
03 - Rinse all vegetables thoroughly. Halve the cherry tomatoes, dice the cucumber into 1/2-inch pieces, dice the red bell pepper, and thinly slice the red onion into half-moons. Roughly chop the fresh parsley. Keep spinach or arugula whole for the base layer.
04 - Open the can of chickpeas and pour contents into a colander. Rinse thoroughly under cold running water for 30 seconds to remove the canning liquid. Shake well to drain excess moisture.
05 - Divide the cooked grains evenly among four serving bowls, spreading them across the bottom. Arrange chickpeas, cherry tomatoes, cucumber, bell pepper, red onion, and leafy greens in sections over the grains.
06 - Scatter crumbled feta cheese and sliced Kalamata olives over each bowl. Sprinkle with fresh chopped parsley. Drizzle generously with the lemon-tahini dressing immediately before serving.