Boil a large pot of salted water. Cook pasta until al dente, according to package instructions.

Drain and rinse pasta under cold water to cool, then spread on a baking sheet to cool completely.

Prepare the vegetables: halve tomatoes, dice cucumber, slice bell pepper, and finely chop onion.

In a small bowl, whisk together olive oil, vinegar, Dijon mustard, garlic, salt, and pepper until emulsified.

In a large bowl, combine cooled pasta, vegetables, and fresh herbs.

Pour dressing over the salad and gently toss until evenly coated.

Add optional ingredients like grilled chicken, feta, or olives for extra flavor and texture.

Garnish with additional herbs and a light drizzle of olive oil before serving.