First things first, grab yourself the ole reliable slow cooker or crockpot. Toss in the beef, as well as everything except the veggies & peppers.
Next, let’s slice the tops off of those peppers. Get as many seeds out as possible lest you live to regret the wrath of chili de arbol. Add to pot once de-seeded.
Grab your onions, quarter them and add to slow cooker. Try to keep everything at the same level, don't pile stuff up in one place.
Next is your garlic. Split into two portions of 10, half goes in now, we will come back to the other half.
Add water to your cooker until ingredients are just submerged. Cook for 3 hours on high.
After 3 hours, fish out the onions, peppers, garlic cloves, and bay leaves. We’re gonna process these bad boys.
In a food processor/blender, add ½ cup of the broth from the crock pot as well as the veggies you just pulled. Pulse until the solids are liquids.
Over the crock pot, use a strainer and a rubber spatula to drain all those delicious juices from the puree. If available, using cheesecloth will make things easier.
After draining, add back about 2 Tbsp of the pureed solids. See Note 1 for why we did this. Cook for 2 more hours on low.
After 2 hours have passed, it’s time to pull out that beef. Once the beef has been pulled, I highly recommend letting the it cool for a couple minutes. Definitely use some gloves.
Rip each piece of beef up into shreds. Be thorough here, it pays dividends in flavor to get each piece broken up properly.
Once everything is shredded, put it back in to cook for at least another 30 minutes (max 1 hour).
After the timer’s gone off, be sure to give this a taste. Add more salt here as you see fit. Make sure to stir thoroughly, then taste, after each addition. AND REMEMBER: you can always add more salt, but once added, you can not take it away.
To serve, get a pan nice and hot (medium heat). Coat your tortilla of choice in the broth, then cook for 1 minute on the first side. Flip, and add some fixings. We went with Monterey jack cheese, our Birria beef, with pickled red onions and mashed avocado.
Our recommendation: Serve with a side of cilantro lime rice.