i used to work with whipped cream litterally pipping bag whipped cream and practice pratise practise,
trick with the cream was i boiled it then poured over chocolate mixed through let set in fridge o/night next day mixer whip it hard into pipping bag and you can push it out and try try try
scrape it bag into the bag and repeat
Though I do recommend practice, practice, practice, I also have used molds with pate a choux. For instance, gougeres. I piped into half sphere molds and froze them in order to stockpile a ton for New Years. They came out perfect and identical.