The Budget101 home page – Budget101.com has a great listing of recipes of things you can make. Your powdered milk may be used like any milk (check the label for for how much water to add to use as milk) or if your going to use dry, try one of the mixes you can make – for example “Cream of Anything” soup.
I’ve not heard of powdered butter – be sure it is not powdered buttermilk. Or there may be directions on the can.
This is a case of one of those leaks – things in your pantry you should know what they are for or they shouldn’t be bought. To cut your bill, start looking at what you need, planning your meals from that list you’ve already made & not buying anything if possible! How many meals could you actually make if you really gave it some thought? If you do need to buy something, make sure it’s on a list & only buy for what you’ve planned for.