- 1⁄2 cup mayonnaise
- 1⁄3 cup prepared white horseradish
- 1⁄2 tsp. garlic powder
- 1 1⁄2 tsp. finely chopped fresh rosemary
- Kosher salt and freshly ground black pepper, to taste
- 2 lb. parsnips (4–5 medium), peeled and quartered
- 2 tbsp. olive oil
Heat oven to 400°. Combine the mayonnaise, horseradish, garlic powder, rosemary, salt, and pepper; cover and refrigerate.
Toss the parsnips, oil, salt, and pepper; spread in an even layer on a baking sheet. Roast for 45 minutes, stirring halfway, until cooked through. Turn oven to broil and cook a further 5 minutes until golden and crispy. Transfer parsnips to a platter and serve with horseradish mayonnaise.