I found this recipe on acouplecooks.com.

tequila, Topo Chico mineral water, lime⁣
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No one knows exactly how Ranch Water came to be, or how it got its name. Some people say a West Texas rancher invented it in the 1960’s. Then it was a word-of-mouth drink until around 2010, when bartenders in Texas started adding it to their menus. ⁣
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Everything I’ve read says that it isn’t really a Ranch Water unless it’s made with Topo Chico – a mineral water from Mexico that is pretty popular here in the Lone Star State. Topo Chico is super fizzy.⁣
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This tastes like Texas summer. I added a dash of simple syrup to mine to cut the tartness a bit (things get too tart for me pretty quickly) and it is perfect. I have three favorite summer coolers now – Ranch Water, Aperol Spritz, and Paloma. Oh, and Greyhound (well, Whippet), too.⁣