In a large pot of water over medium heat, add the asparagus spears and steam until barely tender, about 4 minutes. Drain and set aside.
Meanwhile, make the dressing: Put the egg yolks in a small bowl and break them up with a fork until no clumps remain. Add the mustard, lemon juice, vinegar, smoked paprika, salt and pepper, to taste, and whisk until smooth. Drizzle in the olive oil, while whisking, to make a creamy dressing. Arrange the asparagus on serving plates. Chop the egg whites and sprinkle them over the asparagus along with the lemon zest and capers. Drizzle with the dressing and top with freshly ground black pepper, to taste. Serve warm, room temperature or chilled.
Perfect hard-boiled eggs
Lay the eggs in a single layer in a large saucepan. Cover with cold water by at least 1-inch. Bring to a simmer over low heat and cook for 1 minute. Cover with a lid, turn off the heat, and allow the eggs to sit for 15 minutes. Rinse with cold water.