It’s hard to imagine just how many times a client has sat down at their hair salon and cited they wanted hair like Gwyneth Paltrow’s. Like quite a few hair icons of late, GP is taking the next step in her legendary blonde evolution by embracing her grays. But don’t call it a base bump: Kadi Lee, celebrity colorist and founder of Highbrow Hippie, uses a technique called the smudge (coined by acclaimed Los Angeles–based colorist Lorri Goddard) to achieve Paltrow’s seamless hair-color transition.

Brooklyn-based colorist and educator Emily Claire explains that there’s a significant difference between the two trending root techniques.

“A base bump is great for anyone who wants to shift their natural color a level lighter without using bleach,” Claire says. “Root smudges utilize demi-permanent color to smudge, drag, or flick the base color downward, about one to three inches from the scalp. It creates a depth or shadow, and due to its lived-in appearance, it’s great for low-maintenance color.”

To melt Paltrow’s grays into her golden-blonde strands seamlessly, Lee says she leaves the smudge dye shade on for half of the normal processing time, skirting the harsh line that can break through after highlights are added: “It gives a tiny bit more gray coverage overall, and I’m still able to have the highlights be really bright and golden.”

Lee says she kicked up the Marty Supreme star’s brightness at her last appointment so she’s summer ready too. If you’re considering copying the look, you’re in luck: Smudging is suited for all seasons and almost all hair colors.

“I would recommend it for anyone whose base color needs a bit more life,” she says. “I have clients who are in their 20s who have very neutral, wheat-colored hair, and this technique helps to really warm it up and give it that nice buttery tone that everyone has been loving.”

It’s also ideal for adding a little depth to brunettes with highlights; Lee says that smudging chocolate-toned hair in combination with highlights creates a chestnut variation—“almost like a tortoiseshell comb.” She adds that the method is also light on upkeep thanks to the softer grow-out, which means you can stretch time between appointments.

Claire points out that smudging is generally not recommended for hair with heavy grays because it can result in a high contrast grow-out. But if the silver has just started, maybe it’s time to ask if smudging is in your future.