I'm not sure what a "traditional" Mulligan Beef Stew would include ... but I thought this recipe had some interesting ingredients. It sure looks appealing.
For myself, if I was making this, I would tweak the recipe a bit, excluding some of the ingredients (like fish sauce) and I would add potatoes for sure. I would keep in the poblano chilies, as that's what makes this stew different from what I've made before.
Mulligan Beef Stew - From Woman's Day

INGREDIENTS
4 tbsp. olive oil, plus more for the pan
3 lb. beef stew meat (such as chuck), trimmed and cut into 2" pieces
kosher salt
2 onions, chopped
4 medium carrots (about 12 oz.), sliced 1/4" thick
2 poblano chiles, chopped
2 large cloves garlic, chopped
1 1" piece ginger, peeled and finely chopped
1 bay leaf (optional)
1/2 tsp. ground cumin
1/2 tsp. ground coriander
2 c. dry red wine
1 1/2 tsp. adobo sauce (from a can of chipotles in adobo)
1 28-oz. can crushed tomatoes
2 c. low-sodium chicken broth
1/2 c. coffee
1 tbsp. Worcestershire sauce
1 tsp. fish sauce
1 tbsp. low-sodium soy sauce
1 tsp. honey
Chopped parsley and rolls or bread, for serving
DIRECTIONS
STEP 1: Heat 2 tablespoons oil in a skillet over medium-high heat. Pat the beef dry with paper towels, season with 1/2 teaspoon salt, then cook in batches until browned all over, adding more oil to the pan if necessary.
STEP 2: Wipe out the pan and heat remaining 2 tablespoon oil over medium heat. Add the onions and 1/4 teaspoon salt and cook, stirring occasionally, until the onions begin to brown, about 8 minutes. Add the carrots, poblanos, garlic, ginger, bay leaf, cumin, and coriander and cook, stirring once or twice, until very fragrant, about 2 minutes.
STEP 3: Transfer the vegetable mixture to a 6-quart slow cooker. Add 1 cup wine to the empty pan and scrape all the browned bits off the bottom; transfer to the slow cooker.
STEP 4: Add the adobo sauce and remaining wine to the slow cooker. Stir in the tomatoes, chicken broth, coffee, Worcestershire sauce, and fish sauce. Nestle the beef in the sauce and cook on high until the liquids are steaming and the dish is fragrant, about 45 minutes.
STEP 5: Stir in the soy sauce and honey and cook on low until the beef is tender, 5 to 6 hours. Discard the bay leaf and season with additional salt if necessary. Spoon into bowls, sprinkle with parsley, and serve with rolls, if desired.
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