The phrase "a layer of cool" is correct and usable in written English.
It can be used to describe a certain level of style, attitude, or temperature that is perceived as cool or appealing.
Example: "The new café has a layer of cool that attracts a trendy crowd, with its modern decor and chill atmosphere."
Alternatives: "an air of cool" or "a touch of cool".
Then put down a layer of Cool Ranch flavor Doritos — lightly crushed.
Air normally cools with altitude, but during an inversion warm air settles above a layer of cool air near the surface.
"Corden doesn't put a layer of cool between him and the viewer (or his guests) – he's as affable and sincere as [Jimmy] Fallon, with just a little less goofiness.
Today, she and husband David Reidmiller, a climate scientist, live in Dupont Circle in a 560-square-foot one-bedroom rental with a king-size bed and a homely refrigerator camouflaged under a layer of cool patterned contact paper.
Start by layering the chocolate pudding on the bottom and then a layer of cool whip, caramel drizzle, crushed Samoas cookies and a sprinkling of toasted coconut.
To counteract overheating, many species cool off by flipping sand onto their backs, adding a layer of cool, damp sand that enhances heat loss.
Scientists had feared the worst because a layer of cooled lava had formed over the bubbling magma beneath the volcano's crater, trapping a tremendous amount of pressure.
Two milliliters of warm 1× MEM containing 1% low-melting temperature agarose (SeaPlaque Agarose; FMC BioProducts, Rockland, ME) was then added and mixed with each infection, and infections were gently poured onto a layer of cooled 1% agarose in 1× MEM to create a soft agar suspension.
You can also apply it on top of a layer of cooled ganache.
With no visuals more elaborate than an occasional hand gesture, Ms. Anderson's songs shed a layer of postmodern cool.
Film cooling is used in gas turbines to thermally protect combustor and turbine hot section components by creating a layer of relatively cooler air to insulate the components from the hot freestream gases.
