My GI dietician suggested Casa de Sante because it's a low FODMAP certified brand. I find all protein powders taste kinda "meh," but this one didn't taste horrible--definitely chocolate is better, and it tastes fine, provided I blend it with a banana and peanut butter, and I will usually add some type of berry to bring some brightness, but you can add it to anything. It might depend on the taste you prefer, but I find banana and peanut better have strong enough flavor to mask the aftertaste that all protein powders seem to have.

If you want something ready to go; she also recommended Kate Farms. There are others out there, if you're looking for something low FODMAP. You can Google it.

It's not technically a protein shake, nor is it low FODMAP, but my GI dietician told me it's GI-friendly. It's a meal replacement, so it has a balanced amount of protein vs. carbs/sugars and fats. It's kind of expensive, but my GI doctor writes me an RX for it and my insurance covers most of it.

I take Kate Farms Standard 1.0 in chocolate flavor (I did not like vanilla). It's vegan and GI friendly. It's an enteral formula so can be used in tube feeding or taken orally.

FYI the adult Standard 1.0 formula is the exact same as their Nutrition Shake product. The difference is the Standard 1.0 is considered a medical food--doctors can write a prescription for it. Whereas the Nutrition Shake can be sold OTC (I've never seen it in-store though). The Nutrition Shake comes in Coffee flavor, while the Standard 1.0 does not. Coffee is my favorite flavor though.