Pizza is a food item that is enjoyed by both humans and Smurfs.
Empath: The Luckiest Smurf stories
Biscotti and Culinary both discovered how to make pizza in the Smurf Village in the EMPATH: The Luckiest Smurf story series. While using most of the same ingredients as regular human pizza (cheese, tomato sauce, and dough), Smurf Village pizza lacks the meat toppings and thus uses mostly vegetables and some meat substitutes. The Smurflings created their own pizza using chocolate and smurfmallow as their toppings instead of spaghetti sauce and cheese.
Due to the early discovery of pizza by the Smurfs in the EMPATH story series, it's likely that the story "Greedy's Master Pizza" wouldn't take place during the time-traveling journeys of The Lost Year.