Drain 400 g firm tofu and cut it horizontally into four thin slices (approximately 1cm or 3/8 inch thick).
Wrap them in kitchen paper.
Then wrap with a clean tea towel.
Place them on a plate and weigh down with a heavy object, then rest in the refrigerator overnight.
Preheat a deep pot of cooking oil to 120 °C (248 °F). Take the tofu from the refrigerator, unwrap it and pat it dry with fresh kitchen paper.
Once the oil is heated, add the tofu slices to the pot and fry for 10 minutes, turning halfway through.
Use a mesh spoon to transfer the tofu to a wire rack, then increase your oil temperature to 160 °C (320 °F). Place the tofu back into the oil and fry until lightly golden, turning occasionally for even coloring.
Transfer to a wire rack and allow any excess oil to drain off.
Cool before use or store in a sealed container in the refrigerator for up to 3-4 days. Enjoy with soup, udon or sushi!