Candy pecans: In a skillet over medium heat, combine brown sugar, cinnamon, salt, and water. Stir, letting sugar dissolve, then add pecans and toss until totally coated. Let simmer 5 minutes until sticky, then remove from heat and let cool on a parchment-lined baking sheet in a single layer. (Pecans you don’t use for the salad can be stored in an airtight container up to 1 week.) Assemble salad: In a large bowl, combine greens, apples, candied pecans, blue cheese, and dried cranberries. Refrigerate until ready to dress and serve. Make dressing: In a bowl or glass jar, whisk together apple cider vinegar, shallot, dijon, and olive oil. Season with salt and pepper. Drizzle salad with dressing and toss to combine. Serve immediately.