[REQUEST] Brownie *cake* recipe? (x-posted to r/Baking)

Hey r/recipes!

A local bakery sells a brownie "cake" that I'm obsessed with. Here's a few images from their Facebook page of a finished cake and a cut slice. I emailed the bakery to kindly ask for the recipe, but either my email got lost in the shuffle, or their policy is not to share.

I'm challenging myself to become a better baker and figure out how to make unconventional desserts, and this is a challenge that flummoxes me. Anyone have a recipe for something like this, or any idea how to replicate it?

Here's what I can tell you about it:

• They call it a brownie "cake" simply because it's thick, the crumb is not cakey at all. It's in fact very chewy, dense (in a good way), and gooey. I'd compare the texture to cold, firm cheesecake but with a definite bite.
• The bakery probably uses some sort of dark cocoa, since this cake is never reddish-brown and always very dark.
• The bakery limits it to 6", 8", or 10" cakes, and one "sponge" is usually about 2" to 2.5" high. I imagine you can't make it any bigger because the center won't cook through.

I'll add more comments if I can think of anything else. Any help anyone can provide is greatly appreciated!

bon appetit