Use of a class inside another class

I have got the following code:

.description p span {
  font-style: italic;
}

<div class="description">
  <p>This recipe is from one of my <span class="cor">favorite</span> cakes out there, really <span>delicious</span>...check it out below</p>
</div>

but I want the class in the first span tag to remove all text with italic to red