Boil Pasta: Bring a large pot of salted water to a boil and cook rotini according to package instructions, usually about 8-10 minutes. Drain and rinse under cold water until completely cooled.

Prepare Vegetables: While the pasta cools, chop the cucumber, halve the grape tomatoes, chop the bell pepper, and finely dice the red onion. Aim for uniform pieces for an appealing presentation.

Combine Ingredients: In a large bowl, mix the cooled pasta, chopped vegetables, Italian dressing, crumbled feta, sliced olives, and parsley. Make sure everything is well-coated and season with salt and black pepper to your taste.

Serve or Chill: You can serve the pasta salad immediately for a fresh taste or chill in the refrigerator for about 30 minutes to let the flavors meld beautifully.