Preheat oven to 350 degrees Fahrenheit.
Chop peeled sweet potatoes into ¼ inch sized cubes. Toss potatoes in 1 tablespoon of the olive oil. Sprinkle with salt and pepper. Spread evenly across a baking sheet.
Bake potatoes for 30-45 minutes or until softened and lightly browned.
While the potatoes are baking, mix seasonings (garlic through cayenne) , balsamic vinegar, and vegan Worcestershire sauce in a small bowl.
Place sliced mushrooms in an 8"x8" baking dish and pour marinade over them. Toss to coat the mushrooms evenly in marinade. Cover dish and place in the fridge for 15 minutes, tossing once.
Add the other 1 tablespoon of olive oil to a skillet and heat over medium high, add mushrooms and saute until mushrooms release their moisture and it is cooked off, about 8-10 minutes.
Divide mushrooms and sweet potatoes evenly between 4 tacos.
Serve with guacamole, salsa and fresh cilantro.