Sargento announced its new Reserve Series by delivering pizzas—but hungry consumers will have to wait up to 18 months because that’s how long it takes the cheese to age.

The “World’s Slowest Pizza Delivery” is a partnership with Chicago pizzeria, Big G’s, offering free pies to the first 100 consumers to sign up on Tuesday. The promotion was open exclusively to those within Big G Pizza’s delivery radius and quickly sold out.

Patient fans were given the choice of four pizza flavors, each made with a different cheese from the Reserve Series. The flavor they chose determined how long they have to wait, depending on the age of each cheese. Options included Margherita (4-Month Aged Italian Blend), Apple Bacon Gouda (6-Month Aged Gouda), Chicken Parmesan (14-Month Aged Parmesan) and Mac ‘n’ Cheese (18-Month Aged Cheddar).

While they wait, pizza recipients can track the progress and watch their cheese age via Sargento’s live cheese cam. They, along with anyone that missed their chance at free pizza, can also visit the microsite for a coupon and pizza recipes to make at home.

Sargento is touting its new aged cheeses as “premium,” which has different meanings for different consumers. According to Nielsen research, the most commonly cited reasons for a product being perceived as premium are that it has exceptional quality (54 percent of respondents) and 42 percent said that they were “very willing” to pay a premium for products made with organic or all-natural ingredients.

Sargento has touted itself as “real cheese people” in marketing campaigns that appeal to consumers’ health and authenticity-conscious appetites. This particular activation is designed to illustrate how natural foods like cheese often take a long time to make, which adds to the flavor and quality.

“At Sargento, we believe that good things come to those who wait—especially cheese,” said Stuart Manning, senior marketing manager of Sargento Shredded Cheese in a press release.

The 65-year-old, privately-owned brand reported net sales of $1.4 billion and is in a good position to take advantage of growing consumer appetites for protein. According to Nielsen, dairy sales reached $953 million in the US as of July 2018. Groceries containing an “excellent source,” of protein have become a $22.6 billion industry.

Global cheese sales are expected to reach $118.44 billion this year, according to Transparency Market Research. This growth, compared to $72.5 billion in 2012, is driven by consumer demand for more nutritional cheese and increased sales from the fast-food segment, the report stated.

Pizza, meanwhile, is another growing market, according to PMQ. The US appetite for a hot slice yielded an estimated $45.1 billion, with 41 percent of that income going to independent restaurants like Big G’s Pizza.