Cook the Potatoes

1. Fill a pot with water and bring to a boil. Add the fingerling potatoes and cook for about 4-5 minutes until tender but firm. Drain and let cool before slicing into coins.

Prepare the Eggs

1. Place eggs in a saucepan and cover with cold water by 1 inch. Bring to a boil over medium-high heat, then remove from heat and cover. Let stand for 8 minutes. Transfer eggs to an ice bath to chill, then peel and halve.

Prepare the Salad Base

1. In a large mixing bowl, combine the sliced potatoes, quartered cherry tomatoes, diced green bell pepper, and halved green olives.

Dress the Salad

1. Drizzle olive oil and sherry vinegar over the vegetables. Add chopped parsley and toss everything together until well coated.

Add the Tuna

1. Flake the Spanish tuna and gently fold it into the salad to distribute evenly without breaking the chunks too much.

Assemble the Dish

1. Arrange the salad on individual plates. Top each serving with two halves of a hard-boiled egg and a couple of boquerones.

Final Touches

1. Serve immediately, or chill in the refrigerator before serving to allow flavors to meld.