Baking – Butter substitute for 1 cup of butter for baking

I guess it depends on what the substitution is for.

Certainly if the butter is just for flavour, it's a reasonable substitute (I think I'd use slightly more yogurt). But 9 times out of 10, fat is the main reason the recipe is calling for butter! Yogurt cannot substitute for a fat (butter) because it has very little fat.

If you lower the fat content of a baked good then you'll generally end up with a product much denser and less flakey. So if you feel you must do this for some reason, then I would increase the sugar in the recipe to compensate (sugar inhibits gluten formation and will help to make the result less chewy).

The other thing you'd better keep in mind is that yogurt is naturally sour and will become even sourer when baked at a high temperature. The longer you bake, the more sour it will become, so you might need to amp up the sugar significantly to maintain the proper flavour.

So for the most part, no, yogurt is really not a substitute for butter or any other fat. Obviously this is partly a matter of personal taste, and if you're happy with the result, then continue doing what you're doing - but I think I'd definitely hesitate to eat a cake that was baked with yogurt instead of butter.

It should be OK, especially if you are purchasing already homogenized almond milk. If you are using homemade almond milk, your glaze won't be perfectly smooth, which may or may not bother you.

Your "glaze" is a standard ganache, and it can be, in principle, made with water or any real dairy. The only purpose of the liquid is to change the consistency of the chocolate to something thinner and softer than a chocolate bar. Cream is the standard choice because it imparts a luscioius creaminess. But you can use lower fat dairy, or cultured dairy products, or even water, if you want a slightly different taste.

A nut milk is simply finely ground nuts mixed with water, frequently also sweetened. It has its own taste, but nuts and chocolate are a classic combination, and even if people notice the faint taste, they aren't likely to complain. Texturewise, there will be no problem from adding it to the chocolate.