Microwave tortillas and 1/2 C chicken broth until tortillas are fully hydrated, about 2 minutes. In a food processor place the tortilla mixture, canned tomatoes with their juice, chipotle and sugar and process until smooth, about 1 minute, scraping down sides of bowl as needed. Place in slow cooker.
Pat beef dry with paper towels and season with salt and pepper. Heat oil in a large skillet and brown half of the beef on all sides, about 8 minutes. Place browned beef in slow cooker with the rest of the uncooked beef.
Add onions and 1/4 tsp salt into fat remaining in skillet and cook over medium heat until onions are softened and lightly browed, about 8 minutes, stirring occasionally. (if the pan starts to get too dark add a bit of vegetable oil to the pan). Stir in jalapeños and cook for about 1 minute. Stir in garlic, chili powder, cumin and oregano and stir until fragrant, about 1 minute. Add remaining 1 C chicken broth and scrape any brown bits off bottom of pan. Turn off heat and transfer to slow cooker.
Stir contents of slow cooker to blend together briefly. Cook for 8 hours on low or 4 hours in high, until the beef is fork tender. Stir twice during cooking. Season with salt and pepper to taste.
Optional: Serve with your favorite toppings such as sour cream, cilantro and shredded cheese, and with a side of rice and beans.
Enjoy!