A little trick I've learned when it comes to keto baking is that protein powders can provide some structure that nut flours can't provide on their own. The problem with that, is many people don't tolerate protein powders well. Whey tends to be pretty insulinogenic, meaning your insulin response might be a lot higher than expected for a product so low in carbs. Egg white protein, to me, makes baked goods taste weird. And you tend to need a pretty substantial amount of either to get the desired result, which means your protein is going to be harder to control.

So, my own preference—and my fool-proof secret ingredient when I bake—is to add a wee bit of collagen peptides to my batter. Not only does it provide a little extra structure without a ton of extra protein, it also adds some lightness to the texture, and helps to keep in moisture. That last bit is crucial whenever you're dealing with almond flour, which isn't very good at absorbing on its own.

Now, I know collagen peptides can be pricy, especially the plain kind that are clean without other added ingredients. However, they do have a pretty long shelf-life and a little goes a very long way, so if you grab a small tub and are only using a scoop here and there in your keto baking, it will last you quite a long time. Kind of like xanthan gum or konjac powder. Feel free to omit it, if you really must, but don't be surprised if the muffins are more dense and less moist when they're done baking.