1. Rinse the quinoa under cool water, until the water comes out transparent. Put rinsed quinoa in a medium saucepan. Add water, 1/2 teaspoon salt and 1 teaspoon turmeric. Bring to a boil over high heat. Reduce heat to low, cover, and simmer for 15 minutes until the quinoa is fluffy. Remove from heat and let stand, covered, for 5 minutes. Fluff with a fork. Let cool.
2. Slice the onion into strips, cut pumpkin and zucchini into cubes. Crush the walnuts and finely chop the parsley.
3. In a large skillet heat 2-3 tablespoons olive oil, and the onion and sauté until golden, add pumpkin and zucchini, season with salt and pepper, stir and fry until soft, about 10 minutes.
4. Place the quinoa in a large bowl, add the veggies, crushed walnuts, crumble the cheese, drained tuna, chopped parsley. Squeeze fresh lemon juice, drizzle 1 tablespoon olive oil and mix well.