With a dough hook and the mixer running, add remaining flour and knead another 5 minutes.
If this sentence doesn’t strike you as strange, note that “a dough hook” and “the mixer running” are two different types of attachments to “with”, one a straightforward noun and the other a more complex phrase. Perhaps this is another case of recipe-register creating telegraphic constructions that are easy to WTF.
The linked Language Log posts explain the complexities of grammaticality judgment in cases like these. In fact, it’s the toughness of the judgments that gave these their fond name: you’re not a prescriptivist ruling them out on some theoretical grounds. But you hear them and go “WTF, that’s not grammatical”, so you’re not being a pure descripitivist either by assuming that anything anyone produces is grammatical. And then you find it’s hard to explain why some examples sound terrible (like “The sun makes you hot and sneeze”) and others sound okay or even clever.
I rather like this grammatical WTF; it can be elegant or amusing when used well, and I think Country Living magazine (the recipe’s original source) used it well.