Whisk honey, olive oil, and optional balsamic vinegar together in a small bowl until well combined. Season with salt and pepper to taste. Let it sit while you prep the other ingredients.
Place walnuts in a dry skillet over medium heat. Stir frequently to avoid burning. Remove after 2–3 minutes when fragrant and slightly browned. Let them cool on a plate.
Place mixed greens in a large bowl. Add crumbled goat cheese and cooled toasted walnuts. Drizzle with the prepared honey dressing. Toss gently to combine. You can serve immediately or chill briefly for a crisp, refreshing texture.
