Mix the cumin, chili powder, oregano, black pepper, and salt in a small bowl. Rub the seasoning mixture all over the meat. In a large non-stick skillet, brown the meat on every side for 1-2 minutes to lock in the flavor.
Cut four slits in the meat and shove four pieces of garlic down in each slit.
Combine orange juice, jalapeno, ½ onion, broth, and one clove of garlic in a high-powered blender. Set aside the remaining onion and chop it up.
Pour half of the mix into the slow cooker and then place the steak inside, surrounded by the remaining onion. Then, cover the steak with the rest of the orange juice mixture. If the steak isn't covered all the way, add more broth.
Slow-cook meat on low for 7-8 hours or high for 4-6 hours.
Use two forks to shred the meat. Optional: Spread the shredded beef across a large baking pan and broil it for 5-7 minutes until the top of the meat gets crispy.
To make the lazy guacamole combine one avocado with your favorite salsa. That's it! Assemble tacos with lazy guac and desired amount of meat.