1) Set up
Line a sheet pan with parchment. Set a wire rack on another sheet pan for draining. This keeps things tidy once the frying starts.
Pour 2 to 3 inches of neutral oil into a heavy-bottomed pot or Dutch oven. Heat to 350°F. Keep a thermometer in there if you can. Mochi donuts are quick, so steady heat matters.
Quick safety note: hot oil is not the moment for chaos. Keep kids, pets, and loose sleeves away from the stove.
2) Mix dry
In a medium bowl, whisk together sweet rice flour, cornstarch, sugar, baking powder, and salt until evenly combined.
3) Mix wet
In a small bowl (or a measuring cup), whisk the egg, milk, melted butter, and vanilla.
4) Make the dough
Pour the wet mixture into the dry. Stir with a spatula until a soft dough forms. You are aiming for soft, smooth, and slightly tacky, but still easy to roll. If it feels dry and crumbly, add milk 1 tablespoon at a time.
If it sticks to your hands while rolling, try lightly oiling your palms first. If it is still truly sticky and hard to handle, add sweet rice flour 1 tablespoon at a time. Do not overdo it, since extra flour can make the donuts less bouncy.
5) Shape rings
Divide the dough into 80 small pieces (8 pieces per donut). For extra consistency, aim for about 10 to 12 g per ball. Roll each piece into a smooth ball.
Arrange 8 dough balls in a ring on parchment, with the balls touching. Gently press the sides together so they stick. Repeat to make about 10 donuts. Each ring will be roughly 3 to 4 inches across once fried.
6) Fry
Fry 2 to 3 donuts at a time, depending on pot size. Carefully lift each donut on its parchment and lower it toward the oil, then peel the parchment away with tongs once the dough touches the oil.
Fry for 2 to 3 minutes per side, flipping once, until puffed and pale golden. Avoid deep browning. Adjust heat to keep the oil close to 350°F.
Let the oil come back to 350°F between batches. This is the difference between crisp and greasy.
Transfer to the wire rack to drain and cool for at least 10 minutes before glazing.
7) Make the glaze
Whisk powdered sugar, 2 tablespoons milk, vanilla, salt, and optional melted butter until smooth. Add more milk a teaspoon at a time until you get a thick but dip-friendly glaze that ribbons back into the bowl.
8) Glaze and top
Dip the top of each donut into the glaze, let excess drip off, and set back on the rack. Add toppings while the glaze is still wet so they stick.
Let set for 10 to 15 minutes, then eat one immediately. Quality control.
9) Easy variations
If you want to play, here are a few low-effort upgrades:
- Matcha glaze: whisk 1 to 2 tsp matcha powder into the powdered sugar before adding milk.
- Chocolate glaze: whisk 2 tbsp cocoa powder into the powdered sugar (you may need an extra 1 to 2 tsp milk).
- Espresso glaze: replace 1 tbsp of the milk with 1 tbsp strong brewed coffee or espresso.
- Citrus glaze: replace 1 tbsp milk with lemon or orange juice, and add 1/2 tsp zest.
