Cook the Pasta: Bring a large pot of salted water to a boil. Add the pasta and cook according to package directions until al dente. Drain and rinse with cold water to stop the cooking process. Transfer to a large bowl.
Prepare the Vegetables: While the pasta is cooking, prepare the vegetables. Halve the cherry tomatoes, dice the cucumber and bell pepper, and thinly slice the red onion. Chop the fresh parsley and basil.
Make the Dressing: In a small bowl, whisk together the olive oil, lemon juice, red wine vinegar, Dijon mustard, minced garlic, dried oregano, and red pepper flakes (if using). Season with salt and pepper to taste.
Combine and Toss: Add the cherry tomatoes, cucumber, red onion, bell pepper, parsley, and basil to the bowl with the cooked pasta. Pour the dressing over the pasta and vegetables. Toss gently to combine, ensuring that all ingredients are well coated.
Chill and Serve: Cover the bowl and refrigerate for at least 30 minutes to allow the flavors to meld. Before serving, toss again and adjust seasoning if necessary. Serve cold and enjoy!