Slideshow: Spicy menu launches.

KANSAS CITY — From Southwest to Sriracha, bold and spicy flavors are kicking up mainstream menus.

“There is a fascinating demographic, young males between the ages of 20 and 30, who have taken to hot and spicy products,” said Craig “Skip” Julius, manager of culinary services for Sensient Flavors, Hoffman States, Ill. “And people have noticed. It has started slow, Wendy’s may have been the first to launch a spicy chicken sandwich, but others have jumped on board. Chicken is the vehicle and even McDonald’s new wing products are spicy. It’s a sign of a much greater awareness around the trend.”

The heat wave spans day parts, from Dunkin’ Donuts’ new Spicy Smoked Sausage Breakfast Sandwich and a chipotle breakfast burrito from Sonic Drive-In to burgers, tacos and pizzas offered by such brands as Burger King, Taco Bell and California Pizza Kitchen.

In October, Subway launched its Fiery Footlong collection, featuring chicken melt and steak melt sandwiches drizzled with trendy Sriracha sauce.

“Sriracha is everywhere today,” Mr. Julius said. “The trend is really interesting. For a long time it was Mexican-based chilies — anchos, chipotle, serranos … but now, in the last couple of years, it has really exploded.”

Click for a slideshow of spicy menu launches.