Wash and spin-dry the spring mix; transfer to a large mixing bowl. Rinse the cucumber and, if using an English cucumber with waxed skin, peel if desired. Slice the cucumber lengthwise and thinly slice into half-moons (about 1/8–1/4-inch thick). Halve the cherry tomatoes. Thinly slice the red onion, separate into rings, and if you want a milder onion flavor, soak the slices in cold water for 5 minutes then drain. Add the cucumber, tomatoes, black olives, and sliced onion to the bowl with the spring mix.

Add fresh herbs and season

Roughly chop the parsley, basil, and chives if not already combined, then sprinkle the fresh herb mix over the salad. Add 1/2 teaspoon salt and 1/4 teaspoon freshly ground black pepper to the salad ingredients and toss lightly to distribute (do not dress yet).

Light Herb Vinaigrette

Combine dressing ingredients

In a small bowl or jar, combine 3 tablespoons extra-virgin olive oil, 2 tablespoons fresh lemon juice, 1 tablespoon red wine vinegar, 1/2 teaspoon Dijon mustard, 1/2 teaspoon honey (or maple syrup), and 1/2 teaspoon minced garlic. Add the chopped parsley, basil, and chives (1 tablespoon each). Season the dressing with 1/4 teaspoon salt and 1/8 teaspoon freshly ground black pepper.

Emulsify dressing

Whisk the dressing briskly for 15–30 seconds (or close the jar and shake vigorously for 20–30 seconds) until it thickens slightly and emulsifies. Taste and adjust seasoning—add more lemon juice for brightness, a pinch more salt if needed, or a touch more honey for balance.

Dress the salad

Just before serving, drizzle about two-thirds of the vinaigrette over the salad (reserve the remainder to allow guests to add more). Gently toss the salad with tongs until the leaves and vegetables are evenly coated. Taste and add additional dressing if desired. Transfer to a serving bowl or individual plates and garnish with a few whole herb leaves or an extra sprinkle of chopped herbs.