Q: Why is spaghetti the smartest food?
A: It always uses its noodle!

Explanation: Yum!  Spaghetti!  To “use your noodle” is to use your brain, that is, to think.  Spaghetti is a type of noodle.

This joke plays with the word noodle, both your brain and the pasta.  Now I’m hungry and off to the kitchen I go!