Preheat the oven to 400°F (200°C). Line a baking sheet with parchment paper.
Slice each package of tofu into six pieces. Pat dry. Drizzle evenly with the tamari.
Combine the nutritional yeast, cumin, garlic powder, turmeric, curry powder, and black pepper in a large rectangular food storage container with a tight-fitting lid. Place the sliced tofu in the container and shake gently until all slices are covered. (You might need to open the container and rotate the slices a bit.) Let sit while the oven preheats. (The marinated tofu can be refrigerated for up to 1 day.)
Place tofu on the baking sheet. Spread any extra seasoning mix on top. Bake for 30 minutes, flipping halfway through.
Serve at room temperature or cold from the fridge.