Set a heatproof bowl over a pot of gently simmering water — medium heat. Combine the egg yolks, Marsala wine, and sugar in the bowl and whisk continuously. This part takes patience: about 10 minutes of steady whisking until the mixture reaches "ribbon stage," meaning it falls off the whisk in a thick ribbon rather than dripping. Don't walk away from it. Remove from heat once it gets there and set aside to cool slightly.
While the Zabaglione is cooling, brew about 2 cups of coffee. :et this cool so it is not scalding. If you want to make this into a grown up version, add a splash of coffee liqueur to the cooled coffee.
In 4 glasses or containers, begin to build the layers. Start with a spoonful of zabaglione on the bottom. Quickly dip each ladyfinger in the coffee — quickly is the key word, they turn to mush fast — and layer about 2 per glass on top of the zabaglione. Don't stress about breaking them to make them fit; nobody's grading you on ladyfinger geometry.Repeat: more zabaglione, more soaked ladyfingers, until the glass is full. Finish each glass with 1–2 tablespoons of whipped topping. This is the swap doing the most visible work — it's a noticeably lower saturated fat option than homemade whipped cream, which makes it a little more heart-friendly without asking you to give up the texture that makes tiramisu tiramisu.
Sprinkle generously with cocoa powder.
Let the glasses sit in the fridge for at least an hour before serving, longer if you can manage the wait, so the ladyfingers soften into the layers properly. Enjoy!