Answer:
I am the red tongue of the earth, that buries cities.
What has a foot but no leg?
I'm often served as a "rack of ..." I'm often smoked or grilled, with bones in, and slathered in BBQ sauce.
What is something yet nothing, but if you fill it up it will disappear?
These are the bumpy parts of your digits
What is big and yellow and comes in the morning, to brighten mom's day?