Blend the Marinade: Blend the dried chipotle peppers, minced garlic, ground cumin, salt, and lime juice until smooth.

Marinate the Beef: Generously rub the marinade on the beef chuck roast and refrigerate for at least 2 hours, or overnight for best flavor.

Slow Cook the Beef: Cook the marinated beef in a slow cooker on low for 8 hours until fork-tender.

Cook the Hash Browns: Cook frozen hash browns in a skillet over medium-high heat until golden brown and crispy, about 30 minutes before serving.

For the Avocado Ranch Dressing: Blend ripe avocados, sour cream, lime juice, chopped cilantro, salt, and pepper until smooth and creamy.

Assemble the Taco Bowls: Layer crispy hash browns at the bottom of each bowl, add shredded barbacoa beef, and drizzle with avocado ranch dressing.