Peel kiwis and slice in half crosswise.
Divide white bean paste into 6 balls.
Set aside while you prepare the mochi dough.
Add shiratamako, sugar, water, and food coloring (if using) in a bowl. Mix to combine.
Transfer mochi batter to microwave safe bowl (I line my bowl with a damp washcloth) and cover well with plastic wrap, another dish, or other cover. Microwave for 2 minutes and 30 seconds.
Carefully dump cooked mochi onto a surface lightly dusted with katakuriko. Divide into six pieces. While you work with one piece, keep the others covered with a damp cloth so they don't dry out.
Flatten one piece (either with a small rolling pin or your hand) of mochi dough and set aside while you prep your kiwi.
Using your hands, stuff each bean paste ball with a half of a kiwi, smoothing the bean paste over the sides. The juiciness of the kiwi makes the bean paste not want to stick, so work quickly in as few movements as possible.
Place your shiroan wrapped kiwi in the center of your flattened mochi dough.
Wrap the mochi around the ball, pinching the edges to seal them. Dust in katakuriko.
Repeat for the rest of the 5 kiwi pieces. Daifuku should be eaten the day they are made.