That's not synesthesia. That's just a taste association that you happened to learn over your life.
Synesthesia would be like associating a specific number with a specific color automatically and involuntarily.
When I said that, I meant seeing the picture triggered all 5 senses involuntarily, like hearing the pepperoni boil, feeling the crust, smelling and tasting the pizza, and seeing it with my own eyes. And yes, in fact, it was kind of involuntary because I DON'T end up being around pizza that much, period.
I think my quirk is when I hear a certain tune, say a music track from a rock artist like 3DG, I end up registering that with a whole picture, like Starry Night from Van Gogh, and all sorts of SE's play in my head. Sometimes it almost sounds real, except with a more ethereal echo to it.