1 tbsp. black peppercorns
10 tarragon sprigs
2 cups plus 3 tbsp. white wine vinegar, divided
3 large egg yolks
1 cup unsalted butter, melted and skimmed
1 tbsp. fresh lemon juice
½ tsp. kosher salt
¼ tsp. black pepper
4 large eggs
2 English muffins, split and toasted
4 slices cured ham (like Parma or Serrano)
1. Combine peppercorns, tarragon and 2 cups vinegar in a small saucepan over medium-high heat. Cook until reduced by half, about 30 minutes. Remove from heat; discard peppercorns and tarragon. Set aside 2 teaspoons vinegar reduction in a small bowl. (Save remainder in an airtight container for another use.)
2. Bring 1 quart water to a simmer in a large saucepan over medium-low heat. Place a heatproof bowl on the pan. Add egg yolks and vinegar reduction; whisk constantly until it forms ribbons when the whisk is lifted.
3. Remove bowl from heat, and slowly whisk in ¼ cup melted butter. Return bowl to saucepan, and cook 2 minutes, whisking constantly. Repeat process with remaining butter until hollandaise mixture reaches a consistency slightly looser than mayonnaise. Whisk in lemon juice, salt and pepper. Set aside.
4. Boil 3 inches of water in a large saucepan over high heat; reduce heat to medium, and maintain at a light simmer. Add remaining vinegar, and stir briskly to form a vortex. Break 1 egg, and slip into vortex. Simmer 2 to 3 minutes, and remove with a slotted spoon. Repeat with remaining eggs.
5. Spread a small amount of hollandaise on each muffin half; top each with 1 ham slice and 1 poached egg. Top with more sauce.