In a large bowl, combine beef, flour, salt, and pepper; toss to coat. Heat 1 tablespoon oil in a large skillet over medium heat until hot. Add in about ⅓ of the beef and brown for about 5 minutes, stirring once or twice. Repeat with remaining beef. Add beef to slow cooker pot.
Meanwhile, roast the poblano over a medium flame, charring all sides. Transfer charred peppers to a ziplock bag and seal; set aside. Allow to steam and cool for 10-15 minutes. Remove pepper, scrape off charred exterior using the blade of the knife. Remove most of the seeds and dice; transfer to the crock pot.
In same skillet used to cook the beef, add remaining tablespoon of oil. Once hot, sauté onions for about 5 minutes, stirring once or twice. Add jalapeño and garlic; sauté for an additional 2 to 3 minutes until peppers start to give off their heat. Add to slow cooker pot.
To the crockpot, add the tomatoes, broth, and seasonings; stir to combine. Cook on high for 4 ½ hours or low for 9 hours. Add beans in the last 20-30 minutes of cooking.