Well, yes and no. A pantry is a big closet or a small room in which you store food. If you are looking for cheap, convenient food, the writer says that nothing in your (or mine, or anyone's) pantry beats ramen.
However, you might not actually have a pantry, you might store your food on a shelf or in a box under your bed. And your "pantry" (wherever and whatever it is) might be empty. The proverbial pantry is kind of the imaginary pantry that you might or might not actually have, but that we all talk about as if you do.
In the specific phrase you've giving the word proverbial means "stereotypical". So the whole sentence would imply something like "If you were to propose alternative ideas for pantries containing cheap and convenient foods, a pantry containing ramen would be an obvious choice." That's a way of putting it using a lot of words, but it captures the meaning of the whole sentence.