Extraction of the Mitragyna speciosa Kratom alkaloids into the tea is show to be facilitated by using powdered material, as this increases the surface area. So if one has crushed or whole dried Kratom leaf, it is best to grind the leaf to a rough powder in a food processor or a coffee grinder.

Place one dose of Mitragyna speciosa Kratom and the equivalent of one mug or coffee cup of water in a small saucepan, and bring to a very light boil, over medium heat. Boil the Kratom for about 15 minutes, until the liquid is reduced to 1/2 a cup.

If one is making more than one dose of Kratom, one should add 1/2 a cup of water per each desired dose.

Hold the saucepan at an angle for a 20 seconds, so that the powdered Kratom will gather, and pour the liquid either through a coffee filter, for fine
powder, or a strainer for coarser ground material, while blocking the Kratom in
the saucepan with a spoon.

Keep the Kratom in the pan, and place anything that fell into the strainer back
in the saucepan, and add another cup of water, boiling down the Kratom on a
light boil for 15 minutes again.

Pour the liquid out as before, using a strainer or coffee filter, and mix the liquid from the first and second Kratom extraction.

This time squeeze the Kratom powder out as much as possible, in order to get all the liquid out of the powder.

Sweeten and flavour to taste, milk diminishing some of the bitterness caused by Kratom’s tannins, sugar and lemon being other common options, and

Here is another basic recipe for making Mitragyna speciosa Kratom tea, inspired by "Sage Student" and Daniel Siebert:

This recipe makes enough Kratom tea for 8 to 16 mild doses, 4 medium-strength doses, or two moderately strong doses (see "Mitragyna speciosa Kratom dosage guidelines")

1.) Take 50 grams of dried, crushed Kratom leaves and put into a pot. To this
add 1 litre of water.
2.) Boil the Kratom leaves gently for 15 minutes.
3.) Pour the resulting Kratom tea through a strainer into a bowl and reserve
the liquid. (squeeze the leaves in the strainer to get most of the liquid out).
4.) Put the Kratom leaves back in the pot and add another litre of fresh water.
Repeat steps 2 and 3.
(after the leaves have been strained a second time, they can be discarded.)
5.) Put the combined liquid from both boilings back into the pot and boil until the volume is reduced to about 100 ml.

(The idea is to boil the tea down to a small volume so that each individual dose can be quickly swallowed. One can boil it down to whatever concentration one is comfortable with. Be careful near the end of the process: if the Kratom tea starts to become syrupy, it may spatter and/or burn.)

The resulting Kratom tea is quite bitter tasting. To minimize the unpleasant taste, gulp it down quickly and then immediately chase it with some pleasant-tasting fruit juice.

If Kratom tea is made from 50 grams of dried leaves, dosage may vary from 1/10th of the tea prepared to yield a threshold dose, to 1/2 the tea for a strong dose, to the whole tea for an extremely strong dose (these doses are indicative only, please see “Kratom dosage guidelines” for further details)

The same general Kratom tea preparation method can of course be used with larger or smaller amounts of Kratom leaves, by simply adjusting the volume of water to weight used.

Mitragyna speciosa Kratom tea can be safely stored in the refrigerator for about five days. It is probably acceptable to keep it a bit longer, but it's better to play it safe and not drink it after five days. By adding about 10% alcohol to the tea will help preserve it. It can then be stored for many months in the refrigerator. This would be one part 40° or 80% proof liquor (vodka, rum, or a similar clear spirit) to three parts of Kratom tea.