Step 1: In a large bowl, whisk together the mochiko flour, tapioca flour, granulated sugar, baking powder, and salt. Make sure there are no lumps in the dry ingredients.
Step 2: In a separate medium bowl, whisk together the mashed silken tofu, egg, whole milk, and vanilla extract until well combined and smooth. Ensure the tofu is fully incorporated and creamy, which is key for the texture of the Japanese Mochi Donuts (Pon De Ring).
Step 3: Pour the wet ingredients into the dry ingredients. Mix with a spatula until a shaggy dough forms, then gently knead by hand for about 2-3 minutes until the dough comes together and is smooth. The dough for your Japanese Mochi Donuts (Pon De Ring) should be soft and slightly sticky but manageable.
Step 4: Divide the dough into 12 equal portions. Roll each portion into a small ball, about 1-inch in diameter. This step is crucial for the signature shape of Japanese Mochi Donuts (Pon De Ring).
Step 5: Arrange 8 small balls into a circle, gently pressing them together to form a ring. Repeat with the remaining dough portions until you have 12 donut rings. Place these shaped Japanese Mochi Donuts (Pon De Ring) on parchment paper squares.
Step 6: Heat about 2-3 inches of vegetable oil in a deep pot or Dutch oven to 325°F (160°C). Use a candy thermometer to monitor the temperature; maintaining a consistent oil temperature is key for evenly cooked Japanese Mochi Donuts (Pon De Ring).
Step 7: Carefully slide 2-3 donuts (still on their parchment paper squares) into the hot oil. The parchment paper will detach naturally as they fry. Remove the paper with tongs. Fry for 2-3 minutes per side, or until golden brown and puffed. Do not overcrowd the pot.
Step 8: Using a slotted spoon or spider, transfer the fried Japanese Mochi Donuts (Pon De Ring) to a wire rack lined with paper towels to drain excess oil. Allow them to cool slightly while you prepare the glaze.
Step 9: Prepare the Glaze: In a shallow bowl, whisk together the powdered sugar and milk (or water/lemon juice) until smooth. Adjust the consistency by adding more liquid for a thinner glaze or more sugar for a thicker one.
Step 10: Dip each slightly cooled donut into the glaze, coating both sides. Place them back on the wire rack to allow the excess glaze to drip off and set. Serve your delicious Japanese Mochi Donuts (Pon De Ring) warm and enjoy the unique texture!