You have been a long-time reader! The Tunnel of Fudge was from the 60s, according to this article (it’s number 5 — scroll down):
If you need the recipe, it was a Pillsbury competition winner and still is posted online by Pillsbury:
https://www.pillsbury.com/recipes/tunnel-of-fudge-cake/8d3b4927-2f71-41a3-9dab-7750f045f252:
Thanks for the link, AW. LOL - Bundt Cakes. When the words are heard can’t help but remember the movie “My Big Fat Greek Wedding” and the character played by Lainie Kazan. The astonishment of a cake with a hole in the middle. The specialty of the era coming from this personal kitchen was the Rum Cake. Every Christmas this was requested and made again, again, and again.
Half Price Books had a few outlets in the Dallas area. My sister and I would meet and spend the afternoon in the store going through their cookbook section. We found some outstanding Southern Living annual cook hooks. One Christmas made their version of Sweet Potato Pecan Praline Souffle. SMACK SMACK. A hit with all and not a bite left on the plates.
Now if only a recipe for lemon chiffon pie would suddenly appear. Actually any chiffon pie would do, not having had a slice in years. They were so good, chilled and eaten in the heat of the summer.