The night before, get your soak on:
Bowl 1: Buckwheat with filtered water and a splash of apple cider vinegar
Bowl 2: Sunflower seeds with filtered water and about a 1 tablespoon of salt Bowl 3: Mushrooms and sun-dried tomatoes with filtered water
The next morning, drain and rinse the buckwheat and sunflower seeds, and place them together in a large bowl. Drain the mushrooms and tomatoes, but keep the soaking liquid and set aside.
Place the mushrooms, tomatoes, garlic, nutritional yeast, oregano, rosemary, and tamari in a blender or food processor and blend on high, adding the soaking liquid from the tomatoes and mushrooms as needed (I used 1/2 cup / 125ml). The sauce consistency should be creamy and thick but spreadable (kind of like hummus).
Preheat the oven to 350°F / 175°C.
Pour sauce over the drained buckwheat and sunflower seeds, toss to coat well, using your hands if necessary. Spread out in an even layer on a standard rimmed baking sheet lined with parchment paper. Bake for 1 hour, turning at 20 minutes, then every 10 minutes until the 1-hour mark. If the mixture is not crispy at this point, turn the oven off and let the mix sit in the oven with the door closed until totally dry.
Remove from the oven and let cool. Transfer to an airtight container and store at room temperature for up to one month.