Couscous Sweet Potato Black Bean Salad

• 3/4 cup couscous
• 1 cup water
• 2 sweet potatoes, peeled and diced (about 3 cups)
• one 14-ounce can black beans, drained and rinsed
• 2 cups baby spinach, cut into small pieces
• 4 ounces crumbled feta cheese
• half a red onion, thinly sliced
• 1/2 cup chopped pistachios (optional)
• black pepper to taste

Lime Basil Vinaigrette

• 1 bunch of fresh basil (1/2 cup packed)
• 1/2 cup olive oil
• juice of 1–2 limes (to taste)
• 1 clove garlic
• 1/2 teaspoon kosher salt
• 1/2 teaspoon red pepper flakes
• 1/4 to 1/2 cup water, if needed