Donald Trump did not like the look of his harried chef’s hamburgers.

It was minutes before the kickoff of Super Bowl XXXII in 1998, and Mar-a-Lago, Trump’s South Florida resort, was overbooked. Wealthy members were fuming about the long line at the grill.

“Give me your apron,” Trump ordered his startled employee. “Let me show you how to make burgers.”

The grill man stood aside as his boss wielded the spatula through most of the game, lecturing throughout — “you can get sick if it’s not cooked enough” — on the fine points of preparing one of his favorite meals.

Trump’s hands-on approach to the business of his grand Palm Beach manor is told in the book “Mar-a-Lago” (Flatiron Books) by Laurence Leamer, out Jan. 29. Dozens of friends, enemies and staffers dish about the president “in his natural habitat.”

It’s the place where he subjected then-girlfriend Melania Knauss to a painfully awkward public dinner in 1999, just months after they started dating. He seated the 29-year-old future first lady with his brassy ex-wife Ivana — and Ivana’s mother, for good measure.

“Melania was quiet to begin with, and she was especially quiet that evening,” a spy recalls.

Whether Trump was hoping to incite a catfight or spark a friendship between his former and current flames, neither woman bit, the source said: “They didn’t talk much to each other.”

Trump is a tough boss to please, as his parade of Cabinet members and White House staffers can attest. At Mar-a-Lago, he found the classic French cuisine of Bernard Goupy, hired as Mar-a-Lago’s executive chef in 2000, a source of constant irritation.

Goupy’s specialty was a gourmet Caesar salad built in an edible cheese bowl, which earned raves from Mar-a-Lago regulars like singer Celine Dion. The chef rolled his eyes at Trump’s idea of salad — a hunk of iceberg lettuce doused in thick dressing.

Six months into Goupy’s tenure, Trump stormed into the kitchen, “swearing like a truck driver,” and filled a bowl with lettuce. He threw croutons on top and doused it with commercial dressing, shouting “Now that’s a f–king Caesar!”

Hours later, a lackey fired the chef, but Dion snapped him up. For the next two years, Goupy served her guests his special Caesar, dubbed “Trump salad” on all her menus.

The singer was far from the only celeb who hung out at the massive mansion.

“All kinds of people used to come here just to relax, LA people, movie stars, musical artists, famous tennis players,” a charter member says. “Whitney Houston, Mary Tyler Moore, Paul Anka, Regis Philbin.”

Trump had bought the crumbling pink palace in 1982 and poured money into its restoration for a decade, planning to use it as his private domain. But after a string of business failures and a very expensive divorce, its $2.5 million annual maintenance costs nearly bankrupted him. The Palm Beach gentry breathed a sigh of relief: They had never taken to the brash New Yorker in the first place.

Then a local lawyer convinced Trump to turn Mar-a-Lago into a members-only resort charging fees — one that, unlike others in the snooty beach community, would admit Jewish and African-American members.

To get the plan approved, Trump mounted a campaign that alternated between charm offensives and multimillion-dollar lawsuits — and quietly swung a key town-council election, too. After a three-year battle, he opened the club in 1995. It was his first foray into politics and set a pattern he would follow two decades later.

“He had taken on a proud, unyielding establishment that largely despised him, and he had never backed off from his attacks,” Leamer writes.

“Mar-a-Lago was Trump’s launching pad,” an insider is quoted as saying. “It was like a Broadway show opening out of town in New Haven.”