Preheat your oven to 350F.
Add sugar to a pot over medium heat, stirring continuously for about 5 minutes. The sugar should melt down and become an amber colour. Once this is achieved, quickly pour the caramel into your baking pan and tilt the pan to make sure it's coated in an even layer. Set aside.
In a blender, add tofu, condensed milk, milk, vanilla, salt, agar and sift in the cornstarch and matcha powder. Blend at high speed until completely smooth, scraping the sides down to ensure no clumps remain. Transfer the mixture into the cake pan (over the caramel).
Transfer the full pan into a larger baking dish, ideally one with walls as high as the pan itself to ensure the pan will be completely submerged. Add water to the baking dish to create a water bath and bake this for 1 hour. Remove from the oven and let set at room temperature until cool. Then, cover with foil and refrigerate for 5 hours or overnight.
When ready to enjoy, place a large plate on top of the pan, carefully (but quickly) flip. Slice and enjoy!