In The Distance with You, a thriller by Chilean author Carla Guelfenbein that won the Alfaguara prize in 2015, and Fever Dream, a fiction by Argentinian author Samanta Schweblin that was shortlisted for the Man Booker International Prize in 2017.

These are books I have not read, so I also want to suggest Isabel Allende’s works that I enjoyed: Island Beneath the Sea, Zorro, and Inés of My Soul. Isabel Allende is considered one of the world’s most widely read Spanish-language authors and has received numerous awards including the National Book Award: Lifetime Achievement Award in 2018 and the Chilean National Prize for Literature in 2010.

Some other suggestions for 21st-century Spanish-language literature are as follows:

1. Yuri Herrera is a relatedly new Mexican author whose fiction titled Signs Preceding the End of the World won the Best Translated Book Award in 2014.
2. Such Small Hands, a fiction novel by Spanish author Andrés Barba, was one of the Guardian's Best Books of 2017.
3. Deep Down Dark: The Untold Stories of 33 Men Buried in a Chilean Mine and the Miracle That Set Them Free by Héctor Tobar is a New York Times Book Review Notable Book.
4. Make Your Home Among Strangers by Jennine Capó Crucet is a A New York Times Book Review Editors's Choice pick and winner of the International Latino Book Award for Best Latino-themed Fiction of 2016.
5. The Devil’s Highway: A True Story by Luis Alberto Urrea was a national bestseller in 2005 and a Pulitzer Prize finalist.

I assume you're interested only in those translated into English, which narrows the list somewhat. This is by no means an exhaustive list, of course, but it should get you started (also...thank you for giving me an excuse to research these books; you just added to my reading list!). :)

1. 2666, by Roberto Bolaño (won several awards, including the National Book Critics Circle Award for Fiction)
2. The Brief Wondrous Life of Oscar Wao, Junot Diaz (won the Pulitzer Prize)
3. The Traveler of the Century, Andres Neuman (won Alfaguara Prize and the National Critics Prize)
4. The Private Lives of Trees, Alejandro Zambra (won the Chile's Literary Critics' Award for Best Novel)
5. The Bad Girl, by Peruvian Nobel Prize in Literature laureate Mario Vargas Llosa 
6. City of the Beasts, Isabel Allende (young adult lit)
7. The Sound of Things Falling, Juan Gabriel Vásquez (winner of the Alfaguara Prize)
8. Red April, Santiago Roncagliolo, (another winner of the Alfaguara Prize)
9. Ways of Going Home, Alejandro Zambra (included because his style just sounds interesting to me)
10. The Feast of the Goat, also by Mario Vargas Llosa