Probably easiest if I just link to a picture first:
Doing some research, this appears to be a Sichuan dish in origin. My main experience with this dish is from the old Wei's Restaurant in Fountain Valley which had a Taiwanese owner. Looking at my searches in flickr, it appears the Taiwanese have co-opted this dish. I loved the dish at the old Wei's. I could eat a whole meal of just steamed rice and the sauce from this dish. Unfortunately, Mrs. Wei sold the restaurant and retired and even though they kept the same items on the menu, they never quite tasted the same. I hear Mrs. Wei came out of retirement a bit to help the new owner improve their dishes, but I haven't been there in years so don't know how the food is these days.
Since then, I haven't had this dish in many years until a few weeks ago. I was getting takeout from Chang's Garden in Arcadia and they had a picture of this dish in the window. The name they use on their menu is Flaming Intestine(!!!). Even though it's a Shanghainese restaurant, their version was quite good.
So this weekend I decided to get an authentic Sichuan version of this dish and drove up to Chung King in San Gabriel. To my surprise they didn't have this item on their menu. I ordered their "Claypot Intestine and Tofu" dish which had the 腸旺 characters in the name, but it's not the same dish. No pig's blood, for one. The dish was good, but just not what I was aiming for.
So now I'm asking for help from Chowhounders to give me pointers on which restaurants in the SGV and elsewhere do a good version of this dish. Thanks in advance!