Okay so I don't know what is going on with my vanilla cupcakes.  I have made my recipe a million times before but for some reason this weekend it wants to be a pain. I have literally thrown away three batches at this point. I thought maybe I was over mixing and getting air in the batter so the next time I was super careful not to over beat. And they still collapsed. Then I thought maybe it was my oven temp was too high, so the third time I baked them at 325 instead of 350. And they still collapses!!! I haven't been opening the oven door and letting the heat out. I'm using the exact same brands I always do. Does anyone have any advice?? 

There can be any number of reasons. First, as a general cupcake rule, you want a hotter oven. This helps them rise faster and form a crust with little runoff. (Typically we turn the temp down after the first 5 or 10 minutes.)

For your current issue, double check your ingredients and measuring. Have you used a different brand of butter or margarine? Different flour or sugar? Correct amount of leavener? New measuring cups or spoons? Or if you use a scale, a problem there? The cupcakes appear to have too much sugar, or not enough flour, or too much leavener. Did you scale up the recipe? Did the cupcakes taste the same or different? 

or leavening might be grainy, aka old, half spent -- put some on a separate dish and it should feel light as a feather -- no resistance at all -- not a bit of graininess --

we julian date everything around here -- and i will usually pitch baking powder that is more than a few months old -- i just do -- very humid here and i hate do-overs -- it's easy, inexpensive insurance -- if i run into a problem, i know it's not my leavening --

are you creaming the sugar, fat & eggs into a smoothy smooth emulsion initially? if you are using that method?

i'm with mimi on it lacking flour