1. Crumble the tofu into a food processor and process for 1 minute. Add the oil and process 1 minute. Add the rest of the ingredients except the arrowroot, and process 3 to 4 minutes, until the mixture is very smooth and creamy. Stop the processor a few times and clean the sides of the bowl with a rubber spatula. Taste and add more sugar for a sweeter whip. Stir the dissolved arrowroot to release any starch that has settled to the bottom. Pour into a small saucepan and cook, whisking frequently over medium heat until the mixture reaches a full boil. It will be very thick and gummy. Immediately remove the saucepan from the stove. Add to the cream and pulse to incorporate. Process until the cream is smooth. Spoon the cream into a container. Cover and refrigerate for 2 hours or longer to allow the flavors to blend. The cream will thicken slightly as it chills but it is not a stiff cream. Assemble the cakes. Use a pastry tip, large straw, or chopstick to poke 3 holes into the bottom of each cake. Remove a plug of cake, but don't go all the way through the cake. 4. Fit a12-inch pastry bag with a star or round (¼ inch opening) tip and fill with cream. Slowly squeeze about one tablespoon into each hole. The cakes will seem to expand. Don't worry if the other side of the cake cracks a little. Refrigerate the filled cakes in a covered container. Serve at room temperature.