Hard-boil the eggs

• Place the eggs in a saucepan and cover with cold water.
• Bring to a boil, then simmer until hard-boiled.
• Cool in cold water, then peel and chop.

Make the egg salad

• In a bowl, mix the chopped eggs with the mayonnaise and mustard.
• Season with salt and pepper and stir in the chives.

Form the cheese taco shells

• Heat a frying pan over medium heat and add a small pile of shredded cheddar.
• Let it melt into a lacy disc, then flip and cook briefly.
• While still hot, drape the disc over a handle or mould to set into a taco shape. Repeat with the remaining cheese.

Fill and serve

• Spoon the egg salad into the cooled cheese shells.
• Serve immediately.