This is not because the temperature of the electric baking pan is not adjusted correctly, nor because the amount of baking soda or baking powder is different.

Your problem lies in dough, which means the key link of dough.

You can't mix noodles with hot water. When we talk about hot water, the boiling point is usually around 90 degrees. After the flour is completely dried, adding old flour (or yeast) and then adding hot water will directly "burn" the fermentation function of old flour (or yeast) and destroy their internal structure. Even if it is left for a long time, the mixed flour never rises, and it still belongs to the state of "dead noodles". I don't know, whether the dough is initiated or not depends on whether it expands or not, and whether the torn dough has a honeycomb shape.

You can't mix noodles with cold water. Cold water, cold to the touch, how can it be mixed with dry flour, yeast (or old noodles) to make dough? It is directly related to the environment, season and water temperature. Using cold water to make the fermentation function of old noodles (or yeast) not play out, which is equivalent to "standing still" No matter how long it lasts, the face will always be a "dead face".

How dare you cook a blank for such a "dead face"? It is suggested to divide the baked hard cake into small pieces, melt it with warm water, add dry flour, warm water and old flour (or yeast), stir the dough, and then make a soft and crisp cake according to the technological process, so as not to waste noodles.