if your into ultralight touring
really the deal here is trying to simply not carry anything
or
at least only the bare essentials.
of course every tour, its route, provisions, caloric demand, etc... all are variables to deal with.
when it comes to cooking... depending on what you can manage to eat, that is calories vs weight
nutrition is a tricky bit...
sometimes (often) its much more efficient to simply not cook
or perhaps its not worth the weight to carry a stove.
being able to utilize a micro fire, set up some rocks, create a draw, and use twigs or small pieces of branch can go a long way.
again... depends on your locale.

if you have to use a stove, and you're not cooking "gourmet" mostly boiling water for the likes of Quinoa, I had gone thru an alcohol stove phase, here is a Pack-a-Feather stove that I grew to really like: http://packafeather.com/stove.html

until one day I decided to start making can stoves, which was not hard to learn, which in turn, became "why do I need to carry a stove when I can just make one when I need it?" so I got pretty good at just digging in a trash can, finding a can, poke some holes in it and viola!

then I decided to use twigs in a can. poke holes in it let it develop a draw and you can get a fairly smoke free (or at least smoke light) fire. again... why carry a stove.

while digging out trash cans, I became picky as to what I was willing to dig thru.
then I realized that most "waste cans", like a waste paper basket, or the ones in the bathroom at a state park, there is a very good chance that there is a stash of new/clean plastic bags in the bottom of the can. just pull aside the bag that is currently in use, and usually park staff has a small stash hidden.

so I started using these plastic bags for all sorts of stuff. namely a ground cloth to sleep on. or to use as a waterproof frame bag liner, etc...

once you change your mindset to simply sourcing from your environment, you start to wonder why you carry anything. if you're on the pavement, every gas station you pass, has sugar, non-dairy creamer, forks, spoons, etc... If you ask a gas station worker for a big piece of plastic, they will more than likely have something laying around!

the one thing I have a tendency to carry is a decent piece of cordage. my favorite is Kelty Triptease, only because its thin, strong and reflective.

I carry 4 MSR Groundhog stakes. typically I use twigs for additional stakes, using the MSR Groundhog stake(s) to make a hole for a twig to fit into.

the last few tours I have completely ditched the thermarest. instead I just sleep on a pile of grass/leaves or whatever. I do lay a ground tarp (whatever that maybe) over the pile.

I've been a big fan of Meal Pack Bars: http://www.mealpack.com/
they are about 440calories each, at about 106gm. for 1lb you get about 600 calories.
Hammer Nutrition Perpeteum is pretty darn awesome. typically I carry at least 1 large water bottle full of powdered Perpeteum which is about 17 scoops. I can manage on about 1 scoop/hr while pedaling. altho that is pretty lean for me. 2 scoops/hr is great.

again, depending on the route
you can get away with the likes of a silnylon tarp
I like Kifaru stuff. I use a ParaTarp
for sleeping I use a Kifaru Woobie, Kifaru Parka
I carry a set of Patagonia Capeline long johns
I also like wool. I simply rinse the base layer, and I typically just let the wool jersey get funky. its amazing how much abuse wool can take.

what you want to avoid are items that do not compress.
frame bags are great, handlebar roll, etc...
ultimately it comes down to carrying as little as possible.