1/2 medium apple, such as Honeycrisp, Gala, or Fuji, thinly sliced
2 hard-boiled eggs, quartered
Directions
Preheat oven to 350°F. Toast walnuts on a rimmed baking sheet, tossing once, until golden brown, 8–10 minutes. Let cool; coarsely chop.
Heat 1 Tbsp. oil in a medium skillet over medium-high. Cook sausage, turning occasionally, until browned on both sides, 3–5 minutes. Transfer to a plate.Meanwhile, whisk horseradish, lemon juice, honey, 1/4 tsp. salt, and 1/8 tsp. pepper in a medium bowl. Slowly whisk in remaining 3 Tbsp. oil in a steady stream. Coarsely chop 2 Tbsp. parsley and stir into dressing.Toss romaine, apple, sausage, and remaining parsley in a large serving bowl. Add two-thirds of the dressing and toss to coat; season with salt and pepper if necessary. Top with walnuts and eggs; drizzle with remaining dressing.
Dressing, without parsley, can be made 3 days ahead. Cover and chill.
