Apparently, besides baking a lot of bread, people have been making this "dalgona coffee" drink during the coronavirus quarantine. Called "dalgona coffee" because the taste is said to be similar to a Korean honeycomb toffee, the trend began in South Korea and has been popularized over the past few months thanks to social media posts. Per wikipedia (which I suppose we can trust on this one), it's "a beverage made by whipping equal proportions of instant coffee powder, sugar, and hot water until it becomes creamy and then adding it to cold or hot milk."
And that's exactly how Maria made it. The verdict: Sweeter than I was expecting, but indeed a treat.