The laid-back Ríos overcame competition from 44 of the best barmen in the world to claim the prestigious title.
"My intention is not to drive the customer crazy," the mixologist said of his prize-winning approach.
"We have to make life easier, not complicate it."
The 37-year-old Ríos was last man standing among the 15,000 hopefuls in 50 countries who entered the demanding contest.
This year's final, the sixth, took place on board the luxury Mediterranean cruise ship Azamara Journey.
Ríos owns and runs Café Kobuk in Barakaldo, in Spain's Basque Country, with his brother.
There, he serves up breakfasts,coffees, beer – and of course, cocktails.
He also works as a barman in Bilbao's "The Jigger Cocktail".
Ríos will be distracted from the café, and his plans to open a new establishment in Bilbao, as he embarks on a year-long global tour as ambassador for the Diageo Reserve brand.
He will also star in a TV show, to be aired in 100 countries, featuring the best moments of the competition.
On top of that, his cocktail creations will feature in a guide book to be published this month.
"I am thrilled and humbled," he said.
"I look forward to the year ahead, meeting my peers, educating new talent, and learning about new cocktail cultures and trends around the globe."
Diageo ambassador Spike Marchant felt that David's café experience had stood him in good stead, saying, "his creativity, technique and sense of hospitality make him an ideal ambassador for our industry."
Ríos told Spanish daily 20 Minutos that he got started "a little bit accidentally" when he was just 18 and the bar where he worked hosted a cocktail party.
Since then his trajectory has seen him work as a sommelier in Michelín 2-starred restaurant Mugaritz and as maître d' in Bilbao's Michelín-starred.Hotel Sheraton.
His title-winning creation, el Ponche de Oro Vasco ('Basque Gold Punch') was a technically demanding cocktail of Johnnie Walker Gold Label Reserve whisky, pineapple juice, grenadine and soda, adorned with an orange slice, anise and mint.
"My creations are based on classic cocktail-making, but with some modern touches," explained Ríos.
David's relaxed approach even extends to his job title and he shrugs it off when people refer to the world's best mixologist as a waiter.
"They never mean it badly."