Cook quinoa according to package instructions. For the Instant Pot: place dried quinoa with 1 1/4 cup stock or water in the pot. Cook on high pressure for 1 minute and quick release the steam carefully. Drain out excess water after either cooking method.
Combine all ingredients in a mixing bowl and stir to toss with the lemon juice and olive oil. Adjust salt and pepper to taste. Serve immediately or store in the fridge, in an airtight container, for 3-4 days.