Apple, Radicchio, Walnut, and Gorgonzola Salad

Name: Apple, Radicchio, Walnut, and Gorgonzola Salad
Prep time: 20 min
Cook time: 5 min
Total time: 25 min
Cuisine: American
Ingredients: 1 cup unsalted walnut halves (roughly chopped); 1 tablespoon unsalted butter; 3 tablespoons maple syrup; 1 teaspoon Aleppo pepper (or 1/4 teaspoon red pepper flakes); 1/4 teaspoon Diamond-Crystal Kosher Salt (or 1/8 teaspoon Morton Kosher Salt or Sea Salt | plus more for garnish); 3 ounces butter lettuce; 4 ounces radicchio (from about 1/2 medium head*); 1 Granny Smith apple (cored and thinly sliced); 1/4 cup hand-crumbled Gorgonzola cheese; 1/2 cup spiced maple walnuts (recipe above); 1 teaspoon stone-ground mustard (or Dijon mustard); 1/2 lemon (juiced); 2 tablespoons extra-virgin olive oil; Salt and black pepper (to taste)