Preshredded potatoes for the rösti are the key to making this crisp pancake quickly. Top with fried eggs and a salad and it becomes a meal.
Heat 1 tablespoon oil in a medium nonstick skillet over medium heat. Add asparagus and 1/4 teaspoon salt. Cook, stirring, until tender, about 3 minutes. Add butter and potatoes; stir to combine. Press the mixture gently into a single layer. Cook until crispy on one side, about 10 minutes.
Slide the rösti onto a clean plate. Drizzle the top with the remaining 2 tablespoons oil, then invert into the pan so the crispy side is up. Cook until crispy on the other side, 8 to 10 minutes more. Slide onto a serving plate and sprinkle with the remaining 1/4 teaspoon salt. Cut into 6 wedges.