Prepare the vinaigrette first: In a small bowl, whisk together the balsamic vinegar, honey, Dijon mustard, and minced garlic (if using). Slowly drizzle in the olive oil while continuously whisking until emulsified. Season with salt and pepper to taste. Set aside to allow the flavors to meld.
Toast the nuts in a dry skillet over medium heat for 3-5 minutes until fragrant and lightly browned, stirring frequently to prevent burning. Remove from heat and let cool.
Wash and dry your greens thoroughly using a salad spinner. Proper drying ensures the dressing will coat the leaves rather than slide off.
Core and thinly slice the apple just before assembling the salad to prevent browning. For an elegant presentation, use a mandoline for paper-thin slices.
Assemble the salad by placing the greens in a large serving bowl. Layer with sliced apples, red onion, pomegranate arils, and toasted nuts.
Sprinkle the crumbled feta cheese over the top of the salad, distributing it evenly for pockets of creamy goodness in every bite.
Just before serving, give the vinaigrette a final whisk and drizzle it over the salad. Toss gently to coat everything evenly without bruising the delicate greens or breaking up the feta too much.