It features two beef patties, American and Monterey Jack Cheese slices, grilled peppers and onions, plus jalapeno ranch sauce.
The burger was first introduced earlier this year and was popular enough to warrant a return as an permanent "All-Time Favorite."
For those with a smaller appetite (and tolerance for salt... a whopping 4050 mg's worth), there's also a smaller, junior version.
Nutritional Info - Whataburger Monterey Melt (407g)
Calories - 1130 (from Fat - 660)
Fat - 74g (Saturated Fat - 27g)
Sodium - 4050mg
Carbs - 58g (Sugar - 7g)
Protein - 55g