Pasta salad is a classic summer side dish, but adding protein (leftover grilled chicken is perfect here) and extra greens makes it a super-satisfying lunch. We use baby spinach, but arugula or baby kale works too. Top with a bright and tangy basil vinaigrette just before serving. The great news is that these easy meal-prep lunches take just 20 minutes to prepare—that's 4 days of lunches in less than 30 minutes.