In a medium saucepan, place the water, and bring to a boil. Add the brown and wild rice, cover, reduce the heat to low, and simmer for 45 minutes. Remove the saucepan from the heat, leave covered, and set aside for 5 minutes to allow the rice to steam. Transfer the rice to a large bowl, fluff with a fork, and allow to cool for 20 minutes. In a small bowl, whisk together the vinegar, mustard, cumin, salt, and pepper. Pour the mixture over the rice and toss gently to combine. Add all of the remaining ingredients, except the kaiser rolls and vegan cheese, and toss gently to combine.

To assemble the sandwiches, begin by slicing the top 1/3 off each of the kaiser rolls, and set the tops aside. Using your fingers, remove some of the bread from the inside of each roll, leaving a 1/2-inch border from the crust edge (save the kaiser roll trimmings for use as breadcrumbs in another recipe). Divide the rice mixture evenly among the 6 kaiser rolls and then sprinkle each with some of the shredded vegan cheese. Replace the tops of each kaiser and transfer them to a large platter for service.

Yield: 6 sandwiches