Answer:
This is variety of pasta formed in narrow tubes, often mixed with cheese powder
What can be opened but cannot be closed?
I'm a pie, but I come with peperoni and cheese
What dish consists of tortilla chips smothered in cheese?
Many people confuse me with a vegetable, but I'm actually a fruit. I'm red when I'm ripe, and I'm sliced and served on burgers.
Those with eyes bigger than their stomach will definitely leave the restaurant with one of them. It is named after a house pet as well.