Hello everybody, So lately I've been wanting to make a fluffy airy cake with some canned peaches in it. Now every time I add the fruit the battery is very runny, which is usually perfect for when I make the box version. But when my cake comes out, it taste great. not as airy as id like or how is should be but its good. Now the test comes to putting the cake in the fridge. When I make it from box, the cake doesn't dense up. But when I do my homemade recipe, the cake is super dense and dries out. How can I fix this, i've looked all over the internet for answers for months now. 

are you using butter in your recipe? if yes -- switch to an oil cake recipe -- that will help

I would recommend buying freeze dried peaches (not just dried) and grinding up to a powder and adding it to your batter.  If you want a few little peachy bits, then add some rough chopped pieces as well.  It will soften while baking.  I have never tried peach (although it sounds great and now I will!) but I add a heaping cup of freeze dried strawberry bits/powder per 5 cups white cake batter. It gives a great fruit flavor without altering the texture or density of the cake.   HTH

Adding any kind of fresh fruit, especially a juicy fruit like peaches or strawberries, will add a lot of moisture and change the texture of the cake.  Personally, I prefer a more dense texture compared to a box mix texture, so the addition of fruit doesn't bother me.  I agree with -K8memphis on changing to a recipe that uses oil instead of butter, if you want your cake to come out of the refrigerator light and fluffy and with yortma on adding freeze dried fruit to get the fruit flavor but retain a light, fluffy texture.