Quinoa: While the chicken is marinading, start with the quinoa. Heat a large, high sided skillet over medium-high heat. When it’s hot, add in the oil and chopped onion. Cook for around 10 minutes, until the onion is soft. Add the chopped red pepper and dry quinoa, cook another 5 minutes until the pepper is soft and the quinoa lightly toasted. Then you pour in 250 ml/1 cup chicken broth, bring it to a boil, cover and then simmer for around 30 minutes. Let rest covered for 5 minutes before fluffing the quinoa with a fork.