Yes, rock sugar can be added to boiled beef tendon.

Ingredients list:

* Dried beef tendon: appropriate amount

* Rock sugar: appropriate amount

Preparation steps:

1. Cut an appropriate amount of cowgrass from the field, dry it in the sun and cut it into small sections.

2. Put the beef tendon into the pot and add appropriate amount of water.

3. After the water boils, reduce the heat to low and continue to cook for about 15 minutes.

4. Add appropriate amount of rock sugar and stir until it dissolves.

5. Continue cooking for about 5 minutes and then turn off the heat.

The above is the method of cooking beef tendon and adding rock sugar. During the production process, you can adjust the amount of rock sugar according to your personal taste to get the desired sweetness.