Method Place the eggs in a saucepan in a single layer and cover them with cold water by 2.5 cm (1 inch).
Bring to a full boil over high heat, then turn the heat off, cover with a lid and leave the eggs in the hot water for 11 minutes.
11 min timer Move the eggs to a bowl of ice water and cool for 5 minutes, then crack and peel them under running water.
For a leaner salad, discard two of the yolks; otherwise use them all. Chop the eggs finely.
Mix the chopped eggs with the Greek yogurt, mayonnaise, Dijon, celery, green onion, smoked paprika and pepper.
Lay spinach on two slices of bread, pile on the egg salad and close the sandwiches. Cut in half and serve, or wrap and chill up to 1 day.
Tips Eggs that are a week old peel more easily than very fresh ones. Swaps Gluten-free: use gluten-free bread or lettuce cups. Storing and reheating The egg salad keeps 3 days in the fridge.