Whenever we see umami our mouths start to water, and this recipe gets even better with a bison burger and rich roasted mushrooms. Nutritional yeast is added to the bison blend to give it a unique and tender texture, and grated Parmigiano-Reggiano is added at the finish for a sharp bite. The best part? The recipe was written with the help of a doctor, so it’s all-natural and good for you, too.
Preheat the oven to 400 degrees. Line a baking sheet with a silicone baking mat or parchment paper. Toss together all of the mushrooms in a large bowl. Add the oil, salt, and pepper, tossing to coat the mushrooms. Arrange the seasoned mushrooms in a single layer on the prepared baking sheet. Bake for 12 to 15 minutes, until soft, lightly browned, and beginning to crisp. When cool, transfer to a lidded container and store in the refrigerator for up to 3 days.
Heat the canola oil in a large skillet over low heat. Add the onions and cook for 30 minutes, stirring often, until they are soft and brown. Let cool, and then store in a lidded container in the refrigerator for up to 3 days.
Put the vinegar, tamari, yeast flakes, and garlic in a blender or food processor and blend until well combined. Remove the feed tube and with machine running, slowly drizzle in olive oil. Blend well until the mixture becomes thick and emulsified, like mayonnaise. Pour the mixture into a lidded jar and refrigerate for up to 2 weeks.
Using your hands, mix the bison, yeast flakes, salt, and pepper in a bowl to combine. Divide the meat into 6 patties. Wash your hands.
Preheat the grill to medium-high heat. Preheat the oven to 400 degrees to reheat the Roasted Mushrooms and Caramelized Onions.
Grill the burgers for 5 to 7 minutes each side, depending on the desired degree of doneness. Toast the buns.
Place the burgers on the buns. Top with the mushrooms and onions and drizzle each with a bit of Umami Sauce. Sprinkle on cheese and serve.