Pricey gourmet hamburgers, costing $15 to $20 each and more, have been all the rage among meat-loving foodies for the last four to five years. At least part of that trend can be attributed to the growing popularity of specialty or custom-chopped hamburger blends.

Hamburger blends created by Manhattan-based LaFrieda Wholesale Meats routinely garner rave reviews from foodies and are considered the gold standard among upscale chefs not just in the Big Apple, but across the country.

“Demand for our ‘boutique’ burger blends has been insane for about the last two years,” Mark Pastore, vice president of LaFrieda told Foodie News. “Everyone wants their own custom mix,” he said.

The company creates about 40 custom chopped hamburger blends for restaurants and hotels in New York City, Chicago, Las Vegas and Miami. In New York, the Shake Shake, Spotted Pig, Blue Smoke and Meer’s City Hall Restaurant are among LaFrieda’s clientele.

Pat LaFrieda III, president of the company, works directly with chefs, often in the wee hours of the morning, to develop the hamburger blends they will serve patrons in a few hours’ time. A low-pressure chopping machine is used to grind small batches of each blend, which keeps the meat coarse and avoids “overworking” it.

Only hand-cut whole domestic muscle cuts of beef such as prime chuck, shoulder clod or brisket from primarily Black Angus cattle raised in Kansas and Kentucky are used, to ensure top quality. Short ribs, American Kobe and dry-aged beef are featured in some blends.

Although the specification for each LaFrieda custom hamburger blend is a closely guarded secret, Pastore was willing to reveal three factors that come into play. They are: the fat to meat ratio; the ratio of different types of meats; and the temperature of the product during grinding. There are no seasonings added to any of the blends.

In addition to hamburger blends, LaFrieda markets an extensive line of fresh and aged beef products including custom-cut steaks.

The company also sells branded pork products as well as custom cuts from pasture-raised heritage breeds such as Hampshire. Frenched Hampshire rack chops, Hampshire pork porterhouse chops, fresh St. Louis ribs and Hampshire pork osso buco are the most popular pork products sold by the company, which buys hogs from Iowa producers.

“The people we work with who buy our products are well-educated and understood that there was no reason for concern as far as eating pork,” Pastore said, referring to the recent H1N1 flu scare.

Veal raised on a strict milk diet by Amish and Mennonite farmers in Pennsylvania, fresh corn-fed lambs from Colorado and fresh Long Island duck also are LaFrieda specialties. Rounding out the lineup is a full line of fresh poultry products from suppliers, including Raised Right, Murray’s Perdue, Allen, Case Farms, Mt. Air and Wampler, which arrives every evening and is shipped out each morning to chef clients, many of whom request specific brands.

The company, which currently processes and delivers about 150 tons of meat each week, was founded in 1922 by Pat III’s grandfather, Pat LaFrieda, who was succeeded in the family business by his son, Pat II. Pat II remains involved in the business but turned day-to-day management over to his son (Pat III) and nephew (Pastore) in 1994.