The lack of a cake button on a rice cooker may be due to the fact that more controls and settings are needed to make a cake, and rice cookers are usually designed to cook or steam rice. While some higher-end rice cookers may offer some additional features, a cake button is not common. If you want to use a rice cooker to bake a cake, you need to know how to transfer simple baking to a rice cooker and prepare the following:

1. Prepare the cake ingredients first: flour, eggs, sugar, baking powder, butter and so on.

2. Make the cake: mix all the ingredients together and stir well, pour into the rice cooker.

3. Adjust the rice cooker: Press the "Cook" button of the rice cooker and wait until the cake turns into a light golden color, then you can insert a toothpick to check it.

4. Steam the cake: Close the lid and re-adjust the rice cooker. It takes about 30-40 minutes to bake the cake, depending on the model of the rice cooker and the size of the cake, and you must be careful not to overcook the cake.

While this method takes some practice and experimentation, it's a convenient alternative, and it's likely that you already have a rice cooker at home, which is even less time-consuming and cheaper to use to make cakes.