Papa John's is ready to give pan pizza another try.

The third-largest U.S. pizza chain is rolling out a pan pizza nationally after about two years of tinkering with everything from the sauce and dough to the way it is prepared in its stores.

The Oct. 10 introduction comes more than a decade after Papa John's began selling a square-shaped pan pizza that was not a hit. The company describes the new version, which is round and comes in its own special black box, as its biggest new product in 10 years.

Chief Ingredient Officer Sean Muldoon said people ask him all the time why the chain does not have pan pizza. Larger competitors Pizza Hut and Domino's sell pan pizza along with other varieties.

"Pan does represent a fairly significant percentage of the overall pizza industry and so we just thought that was a great opportunity," Mr. Muldoon said.

Papa John's got its start in 1984 with hand-tossed pizza and added a thin crust variety in 1996. In Sept. 2005, Papa John's touted Papa's Perfect Pan pizza as "the largest and most significant new product roll-out in the company's history and the first new crust offered by the pizza brand in nearly ten years." That version, launched with a campaign featuring Dan Marino, did not catch on with consumers. About two years ago, Papa John's began seriously thinking about whether to try again.

"This is by far the largest new product launch that we've had in 10 years and by far it's been the most rigorous, deliberative new product development process that we've been through as a system," Mr. Muldoon said.

Details such as a thicker sauce and the type of dough being used were reworked, he said. Then, Papa John's had to figure out how the pan pizza could be cooked in stores with a mix of oven configurations. At stores with three ovens, for example, one could be dedicated to the pan pizza. Some stores had to purchase new ovens. At other locations, the most complex scenario involved testing to adjust the time and temperature to be able to cook the different types of pizza, Mr. Muldoon said.

Papa John's has been testing the pizza since May in markets including its hometown of Louisville, Ky., along with Lexington, Ky., Denver, Houston, Ft. Wayne, Ind. and Evansville, Ind.

Without divulging specific targets, Mr. Muldoon said Papa John's has high aspirations for the pan pizza and wants it to make up a double-digit percentage of orders. It still expects the hand-tossed variety with which the business began to be its top seller, but believes pan pizza will outpace thin crust.

In test markets, pan has outsold thin crust. A significant number of customers who ordered the new version were new to the chain, Mr. Muldoon said.

Papa John's is promoting the new pizza in a commercial featuring Peyton Manning.

The retired quarterback introduces food that guests bring to a football viewing party much as players are announced before a game. Houston Texans player J.J. Watt brings a cheese plate from his home state of Wisconsin, followed by Papa John's founder John Schnatter, who of course carries a pan pizza from Louisville, Ky.

The pizza has an introductory price of $10 with a choice of three toppings. Before the full campaign launch, Papa John's teased the new pizza with an image of a black box, the line "Something Better is coming" and the date 10/10/16 on social media.

10/10/16 pic.twitter.com/58EtEM4xJ2

— Papa John's Pizza (@PapaJohns) October 4, 2016

Grey is Papa John's creative agency, with Initiative as its media agency and Edelman handling public relations.