How to Make It
Set the tofu on a cutting board and top with a cookie sheet and 2 or 3 heavy cans. Let stand for 1 hour, or until the tofu is very firm and the liquid has been pressed out. Pat the tofu dry.
Meanwhile, in a small bowl, whisk the jalapeño jelly with the ketchup, soy sauce, sesame oil and 1 tablespoon of the lime juice. In a large bowl, mix the sugar with the garlic and minced jalapeño. Using the side of a spoon, mash the mixture to a paste. Add the fish sauce and the remaining 1 tablespoon of lime juice. Stir in the jicama, carrots, cilantro and mint.
Light a grill. Brush the tofu and the cut sides of the rolls with the vegetable oil. Lightly grill the rolls, about 2 minutes. Grill the tofu over a hot fire until lightly charred, 8 to 10 minutes. Brush on the jalapeño jelly glaze and grill, turning and brushing until nicely glazed, 2 to 3 minutes longer.
Spread a thin layer of mayonnaise on both halves of each roll. Mound the jicama slaw on the rolls and top with the tofu steaks. Close the sandwiches, cut in half and serve.