Rinse the quinoa through a fine sieve under running water for about a minute. Transfer the quinoa and 1 1/2 cups water to a 2 quart saucepan. Bring the mixture to a boil. Reduce the heat to low, cover the saucepan, and simmer the quinoa for 15 minutes. Fluff the quinoa gently with a fork, re-cover, and allow it to steam for 5-10 minutes. This step can be done a few hours in advance, or you can cook the quinoa a day or two in advance and store it in an airtight container in the fridge until you're ready to make the salad.
When the quinoa is ready, add it, along with all other ingredients, to a mixing bowl. Taste and adjust the vinegar, olive oil, salt and pepper to taste. Serve.