Starting Wednesday, Southern California Big Mac fans can satisfy their craving without leaving their driveway.

McDonald’s has launched doorstep delivery through UberEats at 375 restaurants in Orange, Los Angeles and Riverside counties. With the exception of soft-serve ice cream orders and promotional items, the full McDonald’s menu is available through the fast-growing delivery division of Uber.

Third-generation McDonald’s operator Todd Horner, whose family runs 34 Southern California restaurants, said McDelivery allows the chain to get “our meals into people’s hands that may not be able to make it into the restaurant.”

McDonald’s restaurants in Southern California are among the first in the nation to launch delivery. The world’s largest burger chain is expected to expand the service over the coming months in other regions.

Meeting consumer demand for delivery comes as McDonald’s tries to stay one step ahead of its biggest fast food rivals: Burger King, Wendy’s and Jack in the Box.

San Diego-based Jack in the Box launched delivery of its entire menu in late March through a partnership with San Francisco-based DoorDash. Of the 856 restaurants testing delivery, 273 are in Southern California — a key market for Jack in the Box, the company said.

Wendy’s is also testing delivery, including in parts of Orange County. Irvine-based Taco Bell has offered delivery through DoorDash for nearly two years.

McDonald’s is joining a number of popular restaurants going with UberEats, one of the industry’s fastest-growing food delivery companies.

Since debuting in 2014 in Los Angeles, UberEats has added thousands of restaurants to its roster including The Halal Guys, Panda Express, The Flame Broiler, Umami Burger, Slater’s 50/50, Lemonade, Ruby’s Diner and Johnny Rockets.

On the app, pizza, Mexican food and burgers are the most popular search categories.

“People in Southern California search for McDonald’s in the UberEats app almost daily, so we’re excited to expand our reach and deliver what they’ve been craving,” UberEats spokesman Allen Narcisse said in a statement.

Postmates, an on-demand delivery service, said the Big Mac is the No. 1 fast-food item craved by its users. (Note: Postmates acts more like a personal courier service by allowing users to create custom shopping orders).

Many of those searching for food delivery are the industry’s next generation of diners: millennials.

The nation’s 75 million millennials, roughly defined as ages 18-34 in 2015, outnumber Baby Boomers. Mobile ordering is among their biggest pastimes.

Market research firm NPD Group reports 1.7 billion deliveries in foodservice visits annually. Young adults are the heaviest users, representing 56 percent of delivery orders.

Compared to other generations, Gen Z and Gen Y are also the most satisfied users of food delivery services, according to NPD.

“If delivery fits a foodservice operator’s business model and it’s operationally feasible, they definitely need to add it on as an option in order to stay competitive,” said Warren Solochek, president of NPD’s Foodservice Practice division.Delivering meals is one of

Delivering meals is one of several strategies McDonald’s has employed to lure today’s experiential-focused consumer. In recent years, McDonald’s has modernized restaurants, made breakfast available all day and added a line of Signature Crafted burgers made with upscale ingredients.

Many of those programs were first tested in Southern California.

Horton, whose family runs 12 McDonald’s stores in Orange County, said the company has evolved to be more accessible and customer-focused. Testing new ideas is necessary to stay relevant.

“Not everything is going to work perfectly, but a lot of good things come out of trial and error,” said the 34-year-old operator. “If we don’t try it, we’ ll never know.”

Of his 34 restaurants, 23 restaurants are participating in UberEats program. Normal UberEats “booking fees” apply. Locally, fees are about $4.99 per delivery.

However, McDelivery customers can get $5 off their first two UberEATS orders by using the following promotional code valid through July 1: FRIES4U