Rinse the spring mix thoroughly in cold water and spin or pat dry until mostly moisture-free. Halve the cherry or grape tomatoes. Peel the red onion, cut in half, then slice very thinly and separate into rings. Measure the cheddar and either shred or cut into small cubes.

Assemble salad

In a large bowl, place the dried spring mix. Add the halved tomatoes and sliced red onion. Sprinkle the shredded or cubed cheddar over the top. Season with the kosher salt and freshly ground black pepper, reserving a small pinch of each to adjust after dressing.

Simple Vinaigrette

Make the vinaigrette by combining the red wine vinegar, Dijon mustard, honey, lemon juice, minced garlic, salt, and pepper in a small bowl or jar. Whisk or shake to combine until smooth. Slowly stream in the extra-virgin olive oil while whisking (or add oil to the jar and shake vigorously) until the dressing emulsifies and thickens slightly. Taste and adjust seasoning with more salt, pepper or a touch more honey or vinegar as needed.

Dress and serve: Drizzle about 2 to 3 tablespoons of the vinaigrette over the assembled salad and gently toss to coat the greens evenly. Add more dressing if desired, tossing lightly to avoid wilting. Transfer to individual plates or a serving bowl. Finish with an optional additional grind of black pepper and a light sprinkle of salt if needed.