Step 1

Position a rack in upper third of oven; preheat to 400°F.

Step 2

Brush both sides of tortillas with 1 tablespoon oil and arrange on a baking sheet. (It's OK if they overlap a bit; they will shrink as they cook.) Bake, turning once halfway, until browned and very crisp, 10 to 12 minutes. Transfer to a wire rack and let cool.

Step 3

Meanwhile, toss cabbage, mango, 1 tablespoon lime juice, cilantro and 1/4 teaspoon salt in a medium bowl. Combine beet, sour cream, garlic, the remaining 1 tablespoon lime juice and 1/4 teaspoon salt in a small bowl.

Step 4

Heat the remaining 1 tablespoon oil in a large cast-iron skillet over medium-high heat. Add tofu, Cajun seasoning and the remaining 1/4 teaspoon salt. Cook, stirring occasionally, until nicely browned, 8 to 10 minutes.

Step 5

Top the tostadas with the tofu, slaw, beet crema and avocado.