Prep the ingredients: Wash and dry salad greens. Thinly slice apples and drizzle with lemon juice to prevent browning. Toast pecans in a dry skillet over medium heat for 3–4 minutes, stirring occasionally until fragrant.
Make the dressing: In a small bowl, whisk together olive oil, apple cider vinegar, honey, Dijon mustard, salt, and pepper until emulsified. Adjust sweetness or acidity to taste.
Assemble the salad: In a large bowl, combine greens, apples, red onion, and toasted pecans. Toss gently to mix.
Add cheese and dressing: Sprinkle crumbled blue cheese over the salad and drizzle with dressing. Toss lightly to coat evenly. Avoid overdressing to keep flavors fresh.
Serve immediately: Best enjoyed right after tossing. If prepping ahead, keep dressing separate until ready to serve.