Spam cookies are a classic "bullshit internet food," I like spam and had some free time so decided to give it a go. I used a typical chocolate chip cookie recipe minus the chocolate chips for the cookie and seared the spam. I tried both the meme-able slice of spam in the middle of a cookie and the more normal cubes of spam mixed in.
It tastes exactly like you would expect it too. If you like spam and like other meaty desert trends (chicken and waffles, candied or chocolate covered bacon, etc), you would probably like it.
I just did a micro-batch of cookies (it made 4) and ate them all, but probably won't make it again. If you made a full sized batch, you would need to refrigerate the leftovers (because of the meat), which would probably make the cookies go stale and the spam go flabby instead of crisp-- so best when fresh.
The slice of spam cookie was more spam- forward if you want something that really makes you say "wow, there is spam in this cookie." But I think the cubes was better and more coherent, with the spam more evenly distributed and a better ratio.