Place eggs in a large saucepan and cover with cold water

Bring water to a simmer over medium heat. Once it has reached a simmer, stir eggs gently to centre the yolks and cook for 7 minutes. Remove eggs and cool under cold tap water or place in a bowl of iced water

Peel and cut in half. Remove yolks and mash. Arrange egg whites on a serving platter

Mix egg yolks with mayonnaise and mustard. Season with salt and pepper. Drain white cocktail onions, reserving brine. Add 1 tablespoon of brine to the egg mixture along with 2 tablespoons of finely chopped white cocktail onions. Mix thoroughly. Spoon into a piping bag fitted with a 2cm star nozzle. Pipe mixture into egg whites. Sprinkle each egg with a pinch of sweet paprika

To serve, halve remaining red, white and green cocktail onions and scatter over devilled eggs