Of all the recipes for the classic Margarita I studied, the smallest amount was 3/4 ounce, including the standard recipe of the IBA (International Bartender's Association). The max was 1 ounce, as I listed, which is, of course, supported by Cointreau, as well as many others. Of course, I hear there are some pretty bad triple secs out there which you might want to cut way back on. I only tested Cointreau and Hiram Walker's "all natural".