He says that you should always ask what yesterday's soup du jour was as well as today's flavour - to see if it's the same. If it is, it's probably not freshly made.
He told Town & Country magazine: "Ask what yesterday's soup du jour was before today's special. It may be the case that it's the soup du month."
Ramsay also warned not to be taken in by cheap Valentine's Day offers at restaurants as he believes it's the worst day of the year to dine out.
He explained: "Valentine's Day is the worst day of the year to go out.
"Busy kitchens with tons of diners means you don't get the true feeling of the restaurant.
"You should be cooking on Valentine's. What's more romantic than a meal cooked for your partner with good bottle of wine?"
The chef also revealed he wouldn't mind if someone was satisfied with their meal at one of his restaurants because "the customer is king".
But he says it's just as important to let the staff know when you've really enjoyed a meal, as well as when it hasn't been up to scratch.
Ramsay was speaking ahead of the launch of the US The F Word, which is based on the hugely popular UK series, with one crucial difference: he won't be swearing.
And instead of the chef cooking a three-course meal for 50 guests, which often included celebrities, instead families will compete in a cook-off competition, with VIP guests judging their efforts.