So this was the first dish made with my new DIY sous vide setup. No quick 30 minute salmon or 45 minute hanger steak for me! Straight to the 36 hour pork belly... though I think not going for the 72 hour (!) version shows some restraint. The recipe I used was from Zen Can Cook, and since I made no adaptations except substitutions based on what I could find at the store, I won't reprint his recipe here (plus you really should click through and see his gorgeous photos). The final dish is udon with some greens and mushrooms which are just blanched in the dashi, all topped with the pork belly (which has been seared and heated through in the oven) and a sous vide egg.
There are essentially three parts to this dish, the pork belly, the dashi, and assembly of the final dish. The pork belly part is obviously the most time intensive, though "hands on time" is pretty minimal. Zen Can Cook adapted his version from Heston Blumenthal (Nathan Myrvhold is the 72 hour proponent), and does so with an overnight cure in salt and spices followed by 36 hours in sake, mirin, and soy sauce. I went with half michiu and half soy sauce with a dash of rice wine vinegar because... well... that is what I had in the pantry. I probably should have added some sugar to match mirin's sweetness, but I thought the flavor as is was quite good so I went with it.
I had two pieces of one pound pork belly so I put each one in a bag with half the liquid and forced out the air by submerging the Ziplocs in water. After preheating the water bath to 144'F (took about an hour with my setup), into the bath the bags went... keeping the sealed ends to the top so that risk of leakage was minimized.
A day and a half later we have our fully cooked pork belly, which I dunked (still bagged of course!) into a bowl of ice water to cool quickly. Why not just put them into the udon immediately? Well, notice how it's all bumpy and buckle-y? No self respecting chef is going to serve those ugly things (plus it's going to inhibit even browning during the sear), so into the fridge overnight those bags go under a nice heavy weight. This was point where I was most worried about not using traditionally vacuum sealed bags, but once cooled all the fat makes the liquid pretty gelatinous and coupling that with doubling over the sealed end worked fine.
Somewhere during this 60 hour period (12 hour cure + 36 hour sous vide + 12 rest under a weight) you should make your dashi and assemble your other ingredients. If you don't regularly make Asian dishes then this will probably require a trip to the Asian market for things like kombu and bonito.
The sous vide eggs should also get done towards the end of this time period. They're 45 minutes (or up to 4 hours) at 142'F for a runny yolk up to 147'F for more custardy action. If you've never had a sous vide egg, they're different from a normal poached egg because the whites set at a much higher temperature than the yolk cooks. That means you can have a custardy yolk inside of wobbly whites, which can be a little off putting if you don't know what to expect. Personally I found this video helpful in knowing how to handle them.
The next day (or whenever), it's time to assemble your udon and finish off the pork belly. Set your oven to 325'F, slice of a piece the size you need (reserving the pork belly "consomme" to flavor the dashi), and sear it skin side down over high heat in an oven safe skillet until nice and golden brown. Then it's into the oven it goes until it is heated through. How long that takes depends on how big the piece is, but it will most likely be done by the time your udon is ready.
I thought the recipe turned out great, and worked well as a showcase of sous vide cooking. I certainly recommend it to anybody with a sous vide setup.