I made my usual vanilla buttercream and then cooked a bag of frozen raspberries with some sugar (about a cup?…I eyeballed it), until everything became thick. I let the raspberries cool and mixed them into the buttercream. The flavor was so intense and fresh, without being overwhelming!
I also discovered the joys of vanilla bean paste, as opposed to vanilla extract. Again….very strong flavor, but smooth, like good vanilla ice cream! It’s harder to find, and more expensive, but a little bit goes a long way. I think it’s worth it in something like vanilla buttercream, where the vanilla is the star, and it certainly enhanced the raspberry! (For the chocolate cake batter, I still used vanilla extract, but maybe the paste would produce totally new and amazing results there too?)!