Brown the garlic and cayenne peppers on a small cast iron skillet until charred and softened.

Peel and rinse the tomatillos and boil in a medium saucepan until soft like a deflated basketball.

Add the garlic and salt to the molcajete and mash into a paste. Slip the chiles from their stems and mash into the paste as well.

Remove the tomatillos from the water and add to the molcajete. Mash into your desired salsa consistency.

Finely chop cilantro and green onion and add it to the salsa. Stir to incorporate and taste for salt. Season as needed.