I have a pan made for East coast style hotdog buns. It's like a flat bread with bumps in it the shape of Twinkies. You cut through for individual hotdog buns, like cakes. So each pan makes about 10 hotdog buns.There's also a Chicago hot dog bun pan, which seems like it might be easier.
Then squish a filling inside using a pastry bag. You poke a hole in it and like a surgeon deposit the filling by squeezing the bag while simultaneously withdrawing the fill tip through the puncture with machine like precision.Now that I'm poking around over at Amazon, I'm seeing the Kaiser Bakeware Basic Tinplate Eclair/Lady Finger Pan and this Eclair Baking Pan and realizing that Twinkies are eclairs (with the chocolate frosting). And check out the Norpro 3964 Cream Canoe Pan With Bonus 9 Piece Decorating Set:
But the chocolate cupcakes are better. With the white curly frosting on top of thin chocolate ganache. Those can be improved too.
The filling. It's like a whipped cream foam. Lemon custard would be better, or banana. But if you're stuck on white foam then real whipped cream. Or you could jab the can of spray whipped cream in there but then you couldn't control the flavor of it.
Old fashioned cream canoes and traditional French eclairs are simple to make with Norpro's Cream Canoe Pan. Featuring durable heavy gauge construction, the pan has 8 elongated cups that are the perfect shape for baking eclairs or cream filled sponge cakes - homemade Twinkies, anyone?Cream canoes! I Google that term and come up with a recipe for "twinkling good vanilla snack cakes" made in your "a filled cake pan (aka cream canoe pan)." The fall of Hostess is a wake-up call: Get twinkling!
ADDED: You can still buy Tastykake Butterscotch Krimpets, which is what we ate in Delaware in the 1950s and 60s. And here are the Tastykake cream-filled cupcakes, which I think you might find similar to the Hostess cupcakes. No white curlicue on top, but I think you might find they taste better.