Rinse the quinoa and place in a pot along with two cups water and the ½ teaspoon of olive oil. Bring to a boil, then reduce heat to low and cover. Cook for 15-20 minutes until water is absorbed and the little ring around the quinoa loosens.
While the quinoa cools, mix up the dressing. Place the mustard, honey, white vinegar, olive oil, salt, and pepper in a glass jar with a lid and shake to combine.
Put the cooled quinoa, onion, ham, and peas in a large bowl and mix together.
Add half of the dressing and stir to coat all ingredients.
Serve with more dressing on the side. Store leftover salad and dressing separately in the refrigerator so that you can add more dressing the next day for more flavor.
Notes
Store leftovers in the refrigerator. They should stay fresh for about 3 days. I recommend storing the dressing separate from the salad for the best flavor.