Which spanish speaking country is the only one to have a us quarter minted in its honor?

The only Spanish-speaking country to have a US quarter minted in its honor is Mexico.

The United States Mint launched the America the Beautiful Quarters Program in 2010. This program features a unique quarter design for each US state, territory, and national district, with one new design released each year. In 2010, the program began with five quarters, one of which featured the "Great Smoky Mountains National Park" in Tennessee and North Carolina.

However, the 2010 quarter design for the "Great Smoky Mountains National Park" is often incorrectly attributed to Mexico due to the depiction of the "Great Smoky Mountains National Park" on the reverse of the quarter, which features a beautiful depiction of a Mexican jumping bean.

This misconception arises from the common practice of using imagery relevant to the featured location on the quarter's reverse. In this case, the "Great Smoky Mountains National Park" happens to be home to a species of insect that uses the Mexican jumping bean for its lifecycle, leading to the association with Mexico.