I was obsessed with protein coffees for a long time, still am, honestly. I prefer mine hot.
Add a large scoop of chocolate protein to a few ounces of hot water* and shake in a shaker bottle.
Add your heavy cream to a mug (I do 1/2 cup) and “steam,” which for me is 70 seconds at 70% power. Add my coffee and the protein mix. I use an Aerolatté device to whiz everything together and froth it.
As it starts to cool off, I’ll add a bit of peppermint extract and it tastes like a peppermint mocha.
For iced, I use cold brew coffee (either made or purchased) along with a scoop of protein, water, and heavy cream. If I want extra flavor I’ll use some of the sugar-free syrups, I like caramel the best but irish cream, toffee, vanilla, or hazelnut is good.
* Not boiling, just tap hot. I also confirmed with some manufacturers that this does not damage the protein.