Peel the skin of the sweet potato and cut it into 2cm cubes. Soak them in water. Peel the skin of the apple and cut it into 5mm cubes. Put the apple and ★ in a small pot and mix. Let them simmer being careful not to burn them.

Put the sweet potato in a heat-resistant container and add 50ml of water. Put a plastic wrap on top and heat it in the microwave for 8 minutes. If you can easily pierce the sweet potato with a bamboo skewer, strain, mash, and put it in a pot. Add ☆ and stir on low heat.

Remove from heat, add apples, mix, roll into 6 pieces, wrap in plastic wrap and form into "chakin" shape.