Domino’s Pizza is finally releasing its own version of stuffed crust on Monday, aiming to win over the customers who are willing to spend more on the pricey pizza customization.

Adding a stuffed crust to a pizza chain’s menu doesn’t seem like a big deal. But for Domino’s Pizza, it’s more than three decades in the making.

Internal research showed as many as 13 million Domino’s customers ordered stuffed crust pizza from competitors each year.