Step 1: Prepare the Candied Pecans (Optional but Recommended). In a small skillet over medium-low heat, combine 1 cup pecan halves with 2 tablespoons maple syrup and a pinch of salt. Cook, stirring frequently, for 5-7 minutes until the pecans are glossy and the syrup has caramelized. Spread them on parchment paper to cool completely and harden.
Step 2: Whisk the Maple-Dijon Vinaigrette. In a small bowl, combine 1/4 cup olive oil, 2 tablespoons apple cider vinegar, 1 tablespoon maple syrup, 1 teaspoon Dijon mustard, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Whisk vigorously until emulsified and well combined. Taste and adjust seasonings as needed.
Step 3: Prep the Fresh Ingredients. Wash and thoroughly dry 6 cups mixed greens. Core and thinly slice or dice 2 large Honeycrisp apples. If desired, toss the apple slices gently with a teaspoon of lemon juice immediately after cutting to prevent browning. Crumble 4 ounces of feta cheese. Slice 1/4 cup red onion very thinly.
Step 4: Assemble the Salad. In a large salad bowl, combine the mixed greens, prepared Honeycrisp apples, crumbled feta cheese, and thinly sliced red onion. Add the cooled candied pecans.
Step 5: Dress and Serve. Just before serving, pour the maple-dijon vinaigrette over the salad. Toss gently to ensure all ingredients are evenly coated. Serve immediately.