You're going to need about 2 pounds of mushrooms. I really love the Baby Bellas.
Here is the annoying part of this recipe for those of you that hate to cook. You need to chop the hell out of these babies (pun intended). Now, there are a few ways to do it. You can hand chop them like a crazy person, like I did, or you can run them through a food processor. If you choose the sane option, I suggest slicing them with the processor, and then hand chopping them after.
Add them to a large saute pan and start cooking them over a medium-low heat. You don't need any fat, such as olive oil. But you can add it if you like. The mushrooms will release so much water that it literally won't matter.
Once the mushrooms cook down about half way, add in 1/4 cup of taco seasoning. If you have a packet from the store, this is usually a whole packet. I like to hack mine and add in more garlic powder, cumin, and chile powder. I am a total slut for hot food!
Cook the mushrooms for about 5 more minutes.
Now the fun part! And the thing I love most about tacos... you can customize them. I topped mine with some cilantro, chopped red onion, Daiya cheddar shreds, avocado, and some vegan sour cream that I added adobo sauce too. Don't ya just wanna bury your face in my taco? Yah, I meant for that to sound dirty!
If you want to spice up your "sour cream", it only takes about 1/4 cup of adobo sauce per 1 cup of sour cream.