Place vegetables, water, bouillon, seasonings, chipotle peppers and sauce into a large kettle. Simmer for one hour. Remove from heat.
Remove bay leaves and discard. Use slotted spoon to scoop out the vegetables and place in food processor or blender. Allow to cool down for 15 min or so. Add a cup or two of liquid from the kettle, and blend well. Add more liquid if necessary. Pour blended mix back into the liquid and stir.
Heat a tablespoon of oil in a large skillet and sear the elk roast on each side over high heat until browned. Place roast in slow cooker. Pour the sauce over the roast and cook on LOW for 8 hours or until tender.
Remove elk roast from sauce and place on a large cutting board. Slice and chop into small pieces. I like to use a chef's knife for this, or a cleaver, if you have one.
Add a bit of oil to a flat skillet and fry the meat in 3-4 batches to get it a bit crispy. You can skip this step if desired. Place meat into a bowl as you finish frying it, add a few spoonfuls of sauce to it.
Clean skillet if it is really messy. Add a bit of oil. Dip a tortilla into the sauce, lay it on the skillet and quickly add a spoonful of meat on one side, a spoonful of cheese on the other side. Fold together and fry till browned on both sides, flipping occasionally.
Serve warm with extra birria sauce on the side for dipping. Add cilantro and/or chopped onion to each taco if desired.
Notes
I do not know exactly how many tacos this recipe makes. It depends on what size elk roast you use, how full you make your tacos, and so on. But the roast I used made about 20 or so tacos. You can use this recipe for any venison meat: elk, deer, antelope or moose. You can probably use it for bear as well, though I haven't tried it for that yet.Don't be afraid to change things up! If you like it spicier, add more chipotle or other spice. I kept it mild because I have small children who can't handle the spice. The 8 hours is flexible. You can certainly cook it longer if you ahem a bigger roast, or less if it is smaller. The large amount of sauce makes it very forgiving, time-wise. I do not recommend cooking on high. This recipe really needs that low and slow cooking method.