In a large pot, bring salted water to a rolling boil over high heat. Add the rigatoni and cook according to package instructions until al dente, typically around 12 minutes. Once cooked, drain the pasta in a colander and rinse under cold running water to cool it down.

In a medium bowl, whisk together the fresh lemon juice, olive oil, honey, salt, and pepper until the mixture is well combined and emulsified. Set aside to allow flavors to meld.

In a large mixing bowl, add the cooled rigatoni, crumbled feta cheese, dried cranberries, toasted pine nuts, and finely chopped red onion. Toss gently until evenly distributed.

Fold in the baby spinach leaves and the lemon zest into the salad mixture, tossing gently to maintain the spinach's vibrant color.

Drizzle the lemon vinaigrette over the salad mixture, tossing gently until every ingredient is evenly coated.

Cover the bowl and refrigerate for at least 30 minutes to allow flavors to develop.

After chilling, give the salad a gentle toss, taste, and adjust the seasoning. Serve chilled or at room temperature.