American restaurants of the junk-on-the-walls and 'no really, we serve authentic Mexican food, we promise' varieties have, in recent years, taken to serving fajitas and other grilled entrées1 on a 'sizzling' platter. The server bursts in from the kitchen, wearing a lead oven mitt, bearing the apparently still-sizzling meat and/or veggie portion of your meal.
Alerted by the spattering heat-alarm bubbling from your food, the entire restaurant will whip its collective head around, see the column of steam rising from the plate, and exclaim to those nearby, 'Ooh, that looks hot,' or 'That looks so good.'
In reality, however, the food has probably been sitting on a counter for ten minutes while your waiter was getting that jumbo margarita for table three or taking his smoke break.
How do they do it? Well, just before bringing the platter out of the kitchen, the server places a pad of butter on one corner of the marginally-hot plate, which sizzles and pops and smokes like there's no tomorrow.
Restaurants have figured out that the diner's thinking goes like this:
sizzling = hot = just prepared = fresh = authentic = good = I'll come back next week to eat more of it, and buy a logo T-shirt on my way out.
And, as far as can be observed, very few of the diners have noticed the butter faux-sizzle trick.