Wash the eggs, and place them in a deep cooking pot. Top up with enough water to cover the eggs. Bring to a boil over medium heat.
After 10 minutes, lift the eggs out using a slotted spoon and place in cold water.
When the hard-boiled eggs are cool enough to handle, gently crack the shells with the back of a spoon until the entire shell is a network of cracks--do not peel!
Return the eggs to the pot and add in guava leaves, Indonesia bay leaves, shallot skin, garlic skin and salt. Boil until the water has evaporated and eggs are dark brown. I did this step in about 1 hour.
Peel eggs, and set aside.
* During Step 4 above, I normally prepare and make the spice paste, so it’s ready when the eggs are done.