Cut roast into about 10 even pieces without trimming the fat. Pat dry with paper towels, then season all over with salt and pepper.
Heat oil in a large pot or skillet (cast iron is best) over high heat. Sear beef in batches (don’t overcrowd the pan), browning on all sides until deeply browned with a rich, dark color. Beef will release easily when ready to flip. Transfer beef to the slow cooker after searing.
Add all sauce ingredients to a blender. Blend until smooth, about 1 minute.
Pour sauce over beef. Add bay leaves. Turn beef to coat and submerge as much as possible.
Cover and cook on low for 8 hours, until beef is very tender and shreds easily.
Transfer beef to a bowl. Shred with two forks, removing and discarding any large pieces of fat. Spoon some cooking liquid over the beef until nice and juicy. Taste and adjust salt if needed.
Use in tacos, bowls, or burritos with your favorite toppings. My fave: charred tortillas, cabbage tossed with cilantro-lime sauce, beef, avocado, and more cilantro-lime sauce!
Video
Notes
Note 1: Grab a can of chipotles in adobo from the international aisle. Add 2 tablespoons (1 full pepper and then just the surrounding sauce). Freeze leftovers by spreading peppers on a parchment-lined pan, spacing 1/2 inch apart. Freeze for 1 hour, then transfer to a freezer bag. Store for up to 6 months.Storage: Store leftovers in an airtight container up to 5 days. Freeze: Store with a little liquid up to 3 months. Reheat: Warm on stove or microwave with a splash of broth.