Filling:

1/2 cup water
1 cup sugar
14 oz can Adzuki beans
1 tbsp. vegetable oil
Pinch of salt

In a small saucepan, heat water and sugar over high heat until boiling and sugar is dissolved. Remove from heat. Pour into small heat-proof bowl; set aside.
Open the can of Adzuki beans and drain. Pour into the saucepan and mash with a fork. Add 1/3 cup of the sugar syrup and the oil. Return saucepan to medium heat and stir beans until thick and glossy. More of the sugar syrup can be added for extra sweetness.

Mochi
1 1/2 cups glutinous rice flour
1/4 cup sugar
2/3 cups water
2 drops red or green food coloring
1/2 cup cornstarch