How to Make It
Stir together mayonnaise, sour cream, pepper, 3 tablespoons blue cheese, 1½ teaspoons vinegar, and ¼ teaspoon salt in a medium bowl.
Halve tofu lengthwise to create 2 long pieces. Cut each piece crosswise into 6 slices (you should have 12 pieces total, each about ¼ inch thick). Gently press tofu between paper towels to absorb some of the liquid; season with ¼ remaining teaspoon salt. Place cornstarch in a shallow dish. Working with 1 piece at a time, add tofu and turn to coat.
Heat ½ cup oil in a large nonstick skillet over medium-high. Add tofu and cook, turning once, until crispy, about 4 minutes per side. Transfer to a paper towel–lined plate.
Meanwhile, whisk hot sauce with remaining 2 tablespoons oil and 1 teaspoon vinegar in a medium bowl. Add cooked tofu to hot sauce mixture and toss to coat.
Serve each ½ head romaine topped with tofu, celery, radishes, blue cheese dressing, and remaining blue cheese.