How is the color of the cake in the picture adjusted?

Download a PS color matching plug-in ~ You can color with one click

The low-level point is to copy a layer, open: Image-Adjust -HDR color, raise the shadow, lower the highlight, and pull the saturation to avoid color change. Turn on the tone balance again and pull it a little bit yellow.

actually, I suggest that it will be faster for beginners to retouch pictures with their mobile phones.

computer retouching will be complicated. Although it is more powerful, retouching can still be done with a filter like p>voco.

Just adjust the filter concentration and make a highlight shadow.