Cut the firm tofu in half, then divide it into 10 equal pieces. Arrange the tofu in a baking pan, cover with paper towels, place a weight on top, and drain for about 10 minutes.
2
Trim the stems from the shiso leaves and cut each leaf in half.
3
Combine soy sauce, sake, mirin, sugar, vinegar, grated ginger, and grated garlic in a bowl and mix well.
4
Pat the drained tofu dry, dust lightly with cornstarch. Season the pork belly slices lightly with salt and pepper.
5
Place a shiso leaf on the pork, lay the tofu on top, and roll tightly. Dust the seam lightly with cornstarch.
6
Heat a light layer of oil in a skillet for 30 seconds, then arrange the rolls seam-side down. Cover and steam-cook on medium-low heat for 3 minutes.
7
Flip the rolls, cover, and cook on medium heat for 2-3 minutes until the other side is golden. Remove from heat.
8
Wipe away excess oil with paper towels, pour the prepared sauce over the rolls, and cook on medium heat while basting until the sauce thickens. Remove from heat and serve.