Jelly Roll and wife Bunnie Xo are ready to double up their family ... revealing they’re hoping to welcome twins via surrogate in the near future.

Bunnie dropped the bombshell in her new memoir, "Stripped Down: Unfiltered and Unapologetic" -- out now -- revealing they’ve already found "the sweetest woman ever" to carry their babies ... and Bunnie's gearing up to begin IVF stimulation treatments to retrieve her eggs.

The decision didn’t come overnight ... Bunnie says the couple spent the last decade healing --  both stabilizing financially and emotionally -- and finally reached a place where building a future together felt right.

Bunnie writes ... "With the help of the most unselfish woman willing to carry twins for us, we’ll be able to make our baby dreams come true."

Jelly’s already a proud dad to Bailee, 17, and Noah, 9, from previous relationships ... and Bunnie admits she intentionally waited, wanting to have children with someone she knew would be an incredible father.

Their fertility journey actually started back in 2019, when Bunnie learned her fallopian tubes were blocked -- meaning surgery was required, and even then, carrying a baby herself wasn’t guaranteed ... ultimately leading the couple to choose surrogacy.