One Twitter user suggests you can recreate this item by ordering a regular Bean Burrito, requesting "no sauce or onions,” and also ordering a Crunchy Taco.
Then, unroll the burrito, wrap it around the Crunchy Taco, and recreate that Double Decker goodness. A Bean Burrito and Crunchy Taco cost $1.69 each, so this hack totals $3.38.
A Redditor explains another $3.38 hack: "Just order a soft taco with beans instead of beef, no cheese, and no lettuce." Then, order a Crunchy Taco and wrap the tortilla around it.