I hauled myself out of the pool and onto the floor of the cave. I lay there for hours, fetal and sobbing. Nothing made sense - the obelisks in the trench, the teaming millions - no, billions of those things swarming up from the trench. Once I'd hacked up the entire contents of my stomach and cried to the point of dehydration, I decided to end it. There was no way anybody would ever find me down here - there's only manned sub in the world that could get down this far, and its crushed into the size of soup can three kilometers below me, along with what was left of the crew. The lucky ones.

I resolved to find a rock, either to gouge my wrists open or bash my head in with. For the first time I noticed that the cave was lit by an eery glow radiating from the ceiling. And the walls were covered with etchings and pictographs carved deep into the rock, in a slew of styles and scripts I could not identify. The writings were indecipherable, and the pictures depicted strange, alien beings, but the story was easy enough to put together in light of my own experiences.

In each one, a civilization rose. They flourished, discovered, expanded. Eventually they went looking beneath the sea, in search of knowledge and untapped resources. And each time they found Them, the teeming mass my brain had refused to register as possible. Some of the stories ended there, other showed them emerging on the shores, purging and devouring, systematically wiping out every trace.

The far side of the cave still had a few square feet of unused wallspace. On the ground, I found a knife. It's grip was asymmetrical and made of a material I could not identify, and was small and awkward in my hand. The tip was crystalline, and when I tested it, it cut into the rock like it was soft clay. This was no coincidence. They had brought me here. I had little doubt that this cave was the exact epicenter of the signal, the reason we'd come down here in the first place. I began to laugh, and as I laughed I wrote. Why not? Who am I to argue with gods?

Okay, first up. Get a time machine. We're going to make some bread.

Grab some flashy but cheap modern technology. Handgun, airhorn, laser pointer. Dress nice, too. Go back to ancient Sumeria around the dawn of civilization. Declare yourself a living god, and demand you be given grain as tribute. After attaining a sizeable quantity of Tribute Flour, take a stopover in the Himalayas to procure the purest of glacial headwaters. From here you can wing the rest of the bread recipe however you like, although if you decide to use an egg I suggest tracking down the First Chicken and scoring some of those.

Next, for meat, you shall claim the flesh of three of the most deadly and majestic creatures to ever live:
1. The Titan Boa
2. The Megalodon
3. The Honey Badger

All must be slain in single combat with a knife you forged yourself from mysterious alloys found in a meteor under a full moon. You shall sear these meats over the flames of an active volcano (extra rare only, obviously). Then, slice the meat into the thinnest segments possible using a laser.

For cheese, procure the frozen corpse of a lactating wooly mammoth, and extract the milk inside. Reviving the mammoth is not necessary, but highly recommended should time and available technology permit it. Curdle it like the Mongolians, but placing it in a cow's stomach under your saddle and riding across the steppes for 7 days and 7 nights without rest on a jet black Arabian stallion.

For seasoning, invest millions of dollars into producing bizarre transgenic hybrids of every plant you can identify on your spice rack. Apply this and only this Frankenspice.

For sauce, just use some mustard or something this step is only marginally important.

As for vegetables, apply none.

Have a master surgeon layer the meats onto the bread in a perfect interlacing pattern of boa/megalodon/badger. Apply your super-seasoning between each layer. Add the cheese in one contiguous piece that covers the other sandwich perfectly. Toast the sandwich lightly in the oven at 400 F for about ten minutes.

Then, devour it all in one bite while ramping a motorcycle over a pit of tigers and spikes. Triumph.