Bring a large pot of salted water to a rolling boil. Add the rigatoni and cook according to package instructions for 8-10 minutes until al dente. Drain and rinse under cold water.

In a large mixing bowl, combine the cooled rigatoni, fresh spinach, halved cherry tomatoes, crumbled feta cheese, dried cranberries, and diced red onion. Fold gently to combine.

In a small bowl, whisk together the olive oil, fresh lemon juice, Dijon mustard, garlic powder, and a pinch of salt and pepper until emulsified.

Pour the vinaigrette over the salad mixture and gently toss until everything is coated evenly.

Cover the salad and refrigerate for at least 30 minutes before serving to let the flavors meld.