Folks, it really is as easy as adding a teaspoon or two of condensed milk into some strong coffee. I think it's because I haven't had condensed milk in a long time, so I've forgotten its creamy flavor. It seems like the coloring of the coffee is more important than any specific ratio. Good strength is when it looks more like a cappuccino color than a latte color -- "get it done yer neck" :-) It's kind of full circle, as well. When I first started making coffee myself (french roast babey (straight up tastes like cigarettes sometimes)) I would add in a little bit of condensed milk. That was for the first 2 or 3 times, and then I tried drinking it black from then on.
"[Growing up] is hard and nobody understands." // https://www.homestuck.com/story/2391