Place 4 medium nectarines (about 1 lb.), cut into thick wedges, in a medium bowl; drizzle with extra-virgin olive oil and season with kosher salt. Toss to combine; set aside.
Heat 3 Tbsp. honey in a small saucepan over medium until loosened, about 1 minute. Add 2 tsp. coarsely ground pepper and swirl until fragrant, about 15 seconds. Add 1 Tbsp. sherry vinegar or red wine vinegar and swirl to combine; remove from heat.
Arrange 2.5 oz. wedge Danish blue cheese, sliced into thin slabs, 2 oz. sliced jamón Serrano or Iberian ham, and reserved nectarines on a platter. Spoon pepper honey over; sprinkle with flaky sea salt.
