Mash all guacamole ingredients together until smooth, adjust seasoning to taste. Transfer to skull molds and freeze. This can be done several days ahead. Press out of molds to release just before serving.

Preheat the oven to 435°F. Line a rimmed baking sheet with foil and generously oil it with avocado oil, set aside.

Rub the coconut aminos all over the mushrooms and then place them stem side up on one side of the prepared baking sheet. Toss the tomatoes, onion, and garlic in avocado oil and place onto the other half of the baking sheet, ensuring the cut sides of the onion are face down on the tray and the cut face of the tomatoes are face up.

Bake for 30 minutes, or until lightly charred and the mushrooms are browning.

Drain any liquid in the mushroom caps onto the baking tray and transfer mushrooms to a plate lined with paper towels and set aside.

Let the remaining roasted vegetables cool until you can handle them. Transfer to a blender, squeeze the garlic from the peel, if using and discard the peel. Add the chile de arbol and blend until completely smooth. Add salt to taste and adjust the consistency with water (or more oil for a more creamy sauce), as desired to get whatever thickness you prefer.

Transfer mushrooms to serving plates. Spoon salsa cremosa into the middle and then top with a guacamole skull. Serve at room temperature.