Place the flank steak in the slow cooker. Season with salt and pepper (at least 1 tsp. of each)

Add the sliced onion, green bell pepper, minced garlic, orange juice, lime juice, ground cumin, dried oregano, salt, pepper, and vegetable oil to the slow cooker. Mix well.

Cover and cook on high for 4 hours or on low for 8 hours, or until the flank steak is cooked through and tender.

Remove the flank steak from the slow cooker and shred it using two forks.

Heat a large skillet over high heat and add the shredded beef. Cook for 5-7 minutes, stirring occasionally, until the beef is browned and crispy.

Serve the Vaca Frita with rice, beans, or your favorite side dishes, garnished with fresh cilantro. Make it!