Quinoa-and-Spinach Pilaf

INGREDIENTS

• 1 tablespoon unsalted butter
• 1 finely chopped small yellow onion
• 1 minced clove garlic
• 1 cup rinsed quinoa
• 1 1/4 cups water
• 5 cups baby spinach (5 ounces)
• 1 tablespoon grated lemon zest
• Salt and pepper