The printer is still in its earliest stages, so the creators haven't quite perfected the process. Instead of making a classic slice, they're showing off the proper levels of pizza viscosity with similar ingredients: ketchup for sauce, cream cheese for a fine ricotta. The idea's more or less the same, though: the printer lays down a layer of dough from a stock of simple, non-perishable ingredients, then layers the sauce (ketchup) and cheese (cream cheese) on top. A heated surface bakes the pizza.