Making Creamy Pasta Salad is simple. Just follow these easy steps:

1. Cook the Pasta: In a large pot, bring salted water to a boil. Add the rotini pasta and cook according to package instructions until al dente, then drain and rinse under cold water.
2. Prepare the Vegetables: While the pasta is cooking, chop the cherry tomatoes, cucumber, and red onion. Set aside.
3. Make the Dressing: In a large mixing bowl, combine the mayonnaise, sour cream, Dijon mustard, salt, and pepper. Stir well until the mixture is smooth and creamy.
4. Combine Ingredients: Add the cooked pasta, halved tomatoes, diced cucumber, chopped red onion, and shredded cheddar cheese to the bowl with the dressing.
5. Toss Gently: Using a spatula or spoon, gently toss all ingredients together until each piece is well coated with the dressing.
6. Chill: For best results, cover the salad with plastic wrap and chill in the refrigerator for at least 30 minutes. This allows the flavors to meld beautifully.
7. Garnish: Just before serving, sprinkle fresh chopped parsley on top for an added pop of color and flavor.

These straightforward instructions ensure that your Creamy Pasta Salad turns out amazing every time!