Strange Dark Fungus & Underfoot Mushroom Farming Location
Two of the primary ingredients that are used in creating Kaladim Constitutional are Strange Dark Fungus and Underfoot Mushroom. Both of these items are Ground Spawns in Northern Kaladim, the home town of the dwarves.
In the northeastern portion of the town you'll find a small little farm looking place with rows of Mushrooms growing as crops. In between the larger Mushrooms that you see (which can not be picked up) will be really tiny blue or red capped Mushrooms. What you're looking for is shown in the screen shots above. If you couldn't already guess, these are the TS materials that we're after.
This is the only place in the game where you can harvest these two items. I'd estimate about 10 - 15 of each spawn at this one location. They have a relatively quick respawn rate as well, so even if you and someone else is here you're both still likely to fill up on both of these items.