Heat oven to 300°F.
Sprinkle all sides of roast with salt and pepper; set aside.
Heat a large Dutch oven, over medium heat. Add 2 tablespoons oil and heat the oil until it shimmers.
Add onion and sauté about 4-5 minutes or until translucent; stir often. Add garlic, cook 30 seconds; stir continuously. Transfer the onion/garlic mixture to a paper towel-lined plate.
Add the remaining 1-tablespoon oil to the Dutch oven and set heat to medium-high. Set the beef in the pot to sear 4-5 minutes without flipping it over. Once it has a nice sear, turn the roast over and sear the other side.
Sprinkle the roast with taco seasoning, chili powder and cumin. Pour the beer around the roast and cover with a heavy lid.
Cook at 300°F for 3-4 hours, or until beef is fork tender.
Once the roast is tender, carefully shred the roast using two forks.
Set the oven to 350°F and spray a 13x9-inch or two 7x11-inch casserole dishes with nonstick cooking spray.
Spread ¼ cup picanté sauce in the bottom of each dish.
To assemble the tortillas: layer each 1/3 full with shredded beef, sour cream, picanté sauce, sautéed onion/garlic mixture and shredded cheese. Roll tightly and place tortillas seam-side down in the prepared casserole dish.
Spread remaining sauce over the enchiladas, cover with foil and bake 15 minutes. Remove the foil and sprinkle with remaining cheese.
Bake an additional 10-15 minutes or until is melted and enchiladas are hot throughout.
Serve with toppings of your choice.
Enjoy!