You put down the bowl, turn around, and it's already empty. It might seem funny, but eating at that speed brings real problems: gas, regurgitation, choking, and, in large, deep-chested breeds, a greater risk of gastric torsion, which is a veterinary emergency.
Why they eat like that
There are three common reasons, and they are not mutually exclusive. The first is competition: dogs that grew up in a litter or shelter learned that what you don't eat quickly, someone else will. The second is anxiety: the bowl is the only exciting thing all day. The third is simple: meals too far apart, so they arrive famished.
What really works
Slow feeder bowls. The labyrinth forces them to search for food among the channels. It multiplies eating time by five without reducing the amount of food. It's the most direct solution and requires the least management from you.
Divide the meal. Two or three meals a day instead of one greatly reduce voracity. If you go from one to two, do not increase the total amount.
Turn mealtime into work. A dispenser ball or a sniff mat loaded with their daily portion makes the dog earn their food by sniffing and solving. It tires their mind and reduces underlying anxiety.
Eat calmly. If there's another dog in the house, separate them at mealtime. The feeling of competition speeds things up even if there's no real threat.
What you shouldn't do
Putting a large rock in the bowl is a common trick that's a bad idea: dogs that gulp can swallow it. And taking the bowl away halfway through to make them "learn" usually worsens anxiety, rather than reducing it.
When to see the vet
If ravenous hunger appears suddenly in a dog that previously ate normally, or comes with weight loss, excessive thirst, or frequent vomiting, don't treat it as a behavioral problem: make an appointment. There could be a medical cause behind it.