You can obtain this achievement by crafting 10 potions or alchemical mixes at a Workbench. Workbenches can be found at camps, inside your houses in the cities, at random locations in certain areas, or in the fast travel pause area.
To craft consumables such as potions you will need at least one level in Alchemy. The best and fastest way to create 10 would be to choose a potion that only requires level 1 Alchemy and with the least ingredient cost or something with ingredients that you'll have an abundance of after playing. Some good examples would be:
Health Potions: 2 Hawthorne, 1 Beast Essence
Magic Potions: 2 Borage, 1 Beast Essence
Armour Ointment: 1 Beast Essence, 2 Bile
Antidote: 1 Beast Essence, 2 Bile
Resistance Potion: 1 Beast Essence, 2 Bile
Power Potion: 2 Inonotus Hispidus, 1 Beast Essence
Swiftness Potion: 2 Inonotus Hispidus, 1 Beast Essence
Haze Potion: 2 Inonotus Hispidus, 1 Beast Essence
Fury Potion: 2 Inonotus Hispidus, 1 Beast Essence
Most of those ingredients you will acquire a ton of after looting containers in cities, looting enemies and foraging resources out in the wild. You can also purchase any ingredients you need from Merchants.
If you have enough ingredients, you can craft a custom amount at all once. If you select 10 the achievement will pop immediately. If you don't have enough for a single batch of 10, you can do 2 of some, 3 of another, etc. until you hit 10 total and the achievement will pop that way as well.
If you want to obtain the achievement, but don't want to waste any ingredients, save your game before you craft all 10 and then load it back up once your achievement pops. This way you retain your ingredients.
You can also save your game and then craft a ton of potions and drink them all rapidly to also quickly achieve: