Heat the Blackstone griddle to medium. Place the tomatillos on the griddle, cover, and cook until charred on the outside and softened inside, turning as needed.
Add the garlic cloves to the griddle and roast until lightly golden and fragrant.
In a molcajete, grind the dried chiles de árbol until broken down.
Add the roasted garlic and salt, mashing until a smooth paste forms.
Add the roasted tomatillos and mash until the salsa is smooth but still slightly chunky.
Stir in the chicken bouillon, taste, and adjust seasoning as needed.