The phrase "a single cup of" is correct and usable in written English.
It can be used when referring to one specific cup of a beverage, often in contexts related to serving or consumption.
Example: "I would like a single cup of coffee, please."
Alternatives: "one cup of" or "a solitary cup of".
The jobless often sat out cold winter days nursing a single cup of automat coffee for hours.
"As per our information, not a single cup of black tea was drunk in Afghanistan," he said.
Talking with a great deal of intense energy, he used three tea bags for a single cup of tea.
I can't wait for the inevitable Still biopic: a self-important iceberg doling out a single cup of coffee as he expounds on his own greatness.
Many consumers clearly need reminding that filling a kettle to the top to make a single cup of tea makes that cuppa incredibly expensive.
Illy spoke with the writer about the complexity involved in making a single cup of espresso, comparing the process to a symphony.
Among them, EGCG accounts for 50-80% of the total catechin, representing approximately 50 mg in a single cup (100 ml) of green tea [28].
Munkhzorig, who, like most Mongolians, uses only one name, sat on a rug on the floor, reclining against one of three narrow beds that were set against the curved walls of the ger; he kept refilling a single cup, shared by all of us, either with vodka or with Mongolian homebrew — a fizzy, colorless liquid made from cheese curd.
Horse milk is tasty enough -- thick, foamy and so much sweeter than cow's milk that even a single cup seems leavened with spoonsful of sugar.
You go for a quick hit of caffeine and about 60 grams of sugar in a single cup.
For example, according to the U.S. Geological Survey, to make a single slice of bread, single cup of coffee or grow one pound of corn it takes 10, 35 and 110 gallons of water, respectively.
