Wash and dry the mixed salad greens thoroughly, then place them in a large salad bowl.

Gently rinse the fresh blueberries under cool water and pat them dry, then scatter them over the salad greens.

Chop the shelled pistachios into smaller pieces, then sprinkle them over the salad.

Crumble the feta cheese into small chunks and add it to the salad bowl.

Thinly slice the red onion and incorporate it into the salad mixture.

In a small bowl, whisk together the olive oil, honey, balsamic vinegar, Dijon mustard, salt, and black pepper until emulsified.

Drizzle the dressing over the salad and toss gently until everything is evenly coated.

Taste and adjust the seasoning as necessary before serving.