To prepare the eggs place in a pot of cold water, cover and bring to the boil. Remove from the heat and set aside for 10 minutes (do NOT take the lid off). Drain and rinse the eggs for about 30 seconds under cold running water then peel. Do not leave the eggs to cool in water. Simply rinse then peel.
Once your hard boiled eggs have cooled completely you can assemble the recipe.Cut the eggs in half lengthways. Gently squeeze out the yolks and place them in a food processor along with the avocado, mayonnaise, horseradish (if using) and lemon juice.
Puree until smooth and creamy. Stir in most of the chopped chives and season to taste.
Spoon or pipe the filling into the egg halves. Garnish with the remaining chives and refrigerate for 30 minutes before serving if possible.
Cool the eggs completely before making the recipe.
Adjust the amount of lemon juice to your preference. Don't forget to season your filling generously.
If you prefer not to use horseradish use more mayo/yogurt instead. You may also want to add a teaspoon of mustard into the mixture.
In addition to the chives you could also add a tablespoon of chopped dill and 2 tablespoons of parsley.
You can either spoon or pipe (as I have done) the filling mixture into the egg halves. You can just fill the holes or spread the filling over the entire surface of the egg.
Make ahead: boil the eggs ahead and, once cooled, refrigerate for up to 2 days. Peel the eggs just before making the recipe to prevent becoming dry.
If you want to make this recipe ahead I recommend refrigerating the deviled eggs in an airtight container for up to 4 hours. Alternatively make the filling ahead, cover and refrigerate for up to 4 hours before making the deviled eggs.
Best served the day they were made. Chill for 30 minutes before serving if possible.