Remove stems from dried shiitake mushrooms and allow to soak in warm water to soften for about 10 minutes. Usually, soaking time is 20 minutes, but you want them to be about halfway softened (still somewhat tough, as they'll rehydrate further when cooked later). Remove from water, strain and pat dry.

Sauté onion slices until caramelized and fragrant using a little oil, or veggie stock to keep it oil free. They should be slightly golden brown and translucent in colour.

In a food processor, pulse oats and almonds until crushed (careful not to over process them).

Add remaining ingredients (including the onions and mushrooms) and pulse until mixture begins to pull away from the sides of the food processor. If the mixture is too wet, you can add a little more rolled oats to the mixture. The texture should be workable and not too sticky.

With moist hands, form dough into burger patty shapes about 1 inch thick and transfer to a lined baking sheet.

Bake for about 20-25 min at 375F until golden brown, flipping at the halfway point.

Combine all ingredients in a small bowl and mix until smooth. Taste, and adjust by adding more coconut aminos as needed to adjust the salt level.