Put eggs carefully into the base of a medium saucepan (so there is only 1 layer).
Cover with water 2-3cm above the eggs.
Bring to the boil, then turn down to simmer & cook for 4 minutes.
Remove from heat, drain, and run under cold water to cool.
Crack eggshells gently all over with the back of a dessert spoon without removing the shell.
Place eggs back into the empty saucepan, add all other ingredients and cover with water 2-3cm above the eggs. Stir to combine.
Bring mixture back to the boil and immediately turn down to low, simmer and cook for 10 minutes.
Cool to room temperature, transfer into a container and cover. Allow to steep in the refrigerator for at least 12 hours.
Drain, remove shells, and serve.
Tea eggs can be kept up to 4 days in the fridge.