I would call it a predicate adjective. In this use, "tastes" is a linking verb. You could substitute "is" for "tastes"
What part of speech is amazing in the sentence, "The pizza tastes amazing."?
The students of Rm 45
"Tastes" is the linking verb and "amazing" is the subject complement. "Amazing" acts as an adjective complement.
Oops, looks like we crossed posts...
Sometimes, I start an answer and I hold it in my computer because I'm doing something else. By the time I release it, it's 13 minutes later!
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.