Preheat your grill, grill pan, or oven broiler to medium-high heat.
In a pot, combine quinoa and water (or vegetable broth). Bring to a boil, then reduce heat and simmer for 15 minutes or until the liquid is absorbed.
While the quinoa cools, prepare the vegetables and herbs. Toss cherry tomatoes, cucumber, red onion, olives, and parsley together in a large bowl.
Grill the salmon fillets for 6-8 minutes per side, depending on thickness, until cooked through and slightly charred.
In a small bowl, whisk together lemon zest, lemon juice, and olive oil to make a simple dressing.
When the quinoa is cool, add it to the vegetable bowl along with a handful of spinach or greens. Drizzle with dressing and toss gently.
To serve, divide the grain salad among plates and top with grilled salmon. Adjust seasoning with salt and pepper as needed.