Heat the oil in a large sauté pan or deep skillet over medium heat. Add the diced chicken and season with a little salt and pepper. Cook for about 5–6 minutes, turning occasionally, until golden and cooked through. Remove from the pan and set aside.
In the same pan, add the chopped onion and garlic. Sauté for 2–3 minutes until soft and fragrant.
Add the rinsed quinoa, stir to coat it in the onion and garlic mixture.
Pour in the chicken stock and coconut milk, stir well, and bring to a gentle simmer.
Add herbs and cooked chicken back into the pan. Cover with a lid and let simmer for about 15 minutes, stirring occasionally, until the quinoa is tender and most of the liquid is absorbed.
Stir in the baby spinach and lemon juice during the last 2–3 minutes of cooking until wilted and vibrant.
Taste and adjust seasoning with more salt, pepper, or lemon juice if needed.
Serve hot, garnished with fresh parsley.