The Thick Potion in Minecraft doesn't seem to serve any purpose, but there are ways to make use of it.
Instructions in this article apply to Minecraft for all platforms including Windows, PS4, and Xbox One.
How To Make a Thick Potion in Minecraft
Here are the steps for gathering the ingredients and making a Thick Potion.
Make Blaze Powder using 1 Blaze Rod.
Make a Crafting Table using 4 wood planks. You can use any type of plank (Warped Planks, Crimson Planks, etc.).
Drop the Crafting Table on the ground and open it to bring up the 3X3 crafting grid.
Make a Brewing Stand. Put a Blaze Rod in the middle box of the top row and Cobblestones in each box in the second row.
Drop the Brewing Stand on the ground and interact with it to bring up the brewing menu.
Put Blaze Powder in the upper-left box to activate your Brewing Stand.
Put a Water Bottle in one of the three boxes at the bottom of the brewing menu.
Brew up-to three potions at once by adding Water Bottles to the other bottom boxes.
Put Glowstone Dust in the top box of the brewing menu.
Wait for the progress bar to fill. When the process is complete, the bottle will contain a Thick Potion.
Thick Potion Recipe
Here's everything you need to brew a Thick Potion in Minecraft:A Crafting Table (craft with 4 Wood Planks)A Brewing Stand (craft with 1 Blaze Rod and 3 Cobblestones)1 Blaze Powder (craft with 1 Blaze Rod)1 Water Bottle1 Glowstone Dust
What Does a Thick Potion Do in Minecraft?
The Thick Potion doesn't do anything in Minecraft. It's essentially the product of mixing the wrong ingredients. That said, you can set parameters in custom Minecraft maps that require players to make a Thick Potion to progress. For example, you can make it so that players must have a Thick Potion in their inventory to go through a certain door.
It's possible to make a Potion of Weakness by combining the Thick Potion with a Fermented Spider Eye, but there's no reason to do this since you can achieve the same goal by simply adding a Fermented Spider Eye to a Water Bottle.