How to Make It
Cut each tofu block in half lengthwise to make 4 (1 1/2-inch-thick) slabs. Wrap each slab with several layers of paper towels or kitchen towels. Let stand 10 minutes. Remove towels. Place tofu slabs on a rimmed baking sheet. Drizzle tofu with canola oil, and sprinkle with 2 tablespoons of the brown sugar, and 1 teaspoon of the salt.
Process sesame oil, peanuts, vinegar, fish sauce, ginger, garlic, and remaining 1 tablespoon brown sugar and 1/2 teaspoon salt in a food processor until finely chopped, 30 seconds to 1 minute.
Preheat grill to medium-high (400°F to 450°F). Add tofu to grill rack coated with cooking spray; grill, uncovered, until heated through and well-marked, about 3 minutes per side. Remove from grill, and cut each block crosswise into 3 pieces. Arrange on a platter, and drizzle with peanut sauce; sprinkle with cilantro and chiles. Serve with lime wedges.