Boil a large pot of salted water over high heat. Add the rotini pasta and cook until al dente, about 8 to 10 minutes. Drain and rinse under cool water.

In a mixing bowl, combine Greek yogurt, olive oil, minced garlic, cumin, smoked paprika, sugar, salt, and lime juice. Whisk until smooth.

Once pasta is cooled, add it to the bowl with the dressing. Stir in the black beans, corn, spinach, and optional cilantro until well coated.

Taste and adjust seasoning with more salt or lime juice if desired.

Serve immediately or cover and refrigerate for at least 30 minutes before serving.