Side Note: I didn't measure the seasonings; I just sprinkled them evenly all over the entire roast.
Preheat oven to 300 degrees.
Make the shredded beef by sprinkling the chili powder, paprika, coriander, cumin, oregano, sea salt, and freshly cracked black pepper to taste, all over every side of the roast
Heat olive oil in a Dutch oven. Sear the meat in olive oil on all sides.
Spread the Anaheim peppers and garlic around the roast; add beef broth to the Dutch oven, then cover the Dutch oven and place it in the oven. Cook 3-4 hours, flipping the meat halfway through cooking time, until the beef shreds easily. Side Note: Check on the roast every hour to make sure there is plenty of liquid–if it's low, add more beef broth.
Shred the meat with two forks and mix it into the remaining liquid. Taste and re-season if necessary. Set aside and let cool.
To make the taquitos, preheat the oven to 425 degrees. Line a baking sheet with parchment paper or a Silpat mat and coat it with olive oil cooking spray.
Cook the sweet potatoes by adding the olive oil to a small skillet over medium heat; add the diced sweet potato and cook for 8-9 minutes or until tender and golden brown. Remove from heat and set aside.
Wrap corn tortillas in damp paper towels for 1-2 minutes in the microwave to soften.
Prepare the taquitos by placing a bit of shredded beef in the center of the tortilla, adding some sweet potato and a sprinkle of cotija cheese, then rolling.
Place, seam side down, on the prepared baking sheet. Finish rolling the rest of the taquitos, then spray each of them with cooking spray.
Place into the oven and bake for 5-6 minutes, then turn over and cook for an additional 5-6 minutes or until crispy and golden brown.