This is a demonstration of how I go about building a minimum impact fire using the Ti-Tri Caldera cone. The concept applies without a cone as well.
I do not pretend to know the best way to make a small responsible cook fire but this is how I do it. Its pretty simple and straight forward. A lot more could be written but I cant cover everything so I suggest "Bushcraft" by Mors Kochanski. This is how one would go about fire building in the North East and it may not make sense in every environment.Feel free to comment and give constructive advise.
On sustainability, I believe using wood as a fuel source is usually the best choice as far as environmental impact goes. This is assuming that the site you choose is not heavily used or over used causing the available wood to be consumed faster than it can be replaced. A small cook fire in an environment with a surplus of downed wood has less impact I believe than a canister stove using precious metals that are mined and petroleum fuel that is drilled not to mention the manufacture, transportation and marketing of said products.
Here is a pic of most (but not all) of the wood a single oak tree had shed in my yard over the winter months just to give an idea of how potentially fast wood fuel can be regenerated. Admittedly this an old and big tree.
selecting the site
Try to find somewhere free of roots and rocks near the surface of the ground. Roots can catch fire under ground and rocks can hold an amazing amount of heat for a long time. Keep a distance from trees,bushes and fire hazards as well. This is mostly common sense!!
prepare the site
Simply push aside the top layer of duff exposing bare soil. In some places it may be nice to remove the top soil as well, but here the top soil is so thick I would have to dig a ditch so its unnecessary.
gather the wood. You could of course have gathered the wood before hand-like on your way to camp. You need a tinder bundle, fine kindling,coarse kindling,and fuel. It makes sense to have this at the ready before you start the fire!
Here Iam using my Mora to split a damp piece of wood. I also need to spit it up so as to make it small enough to fit in the Ti cone.
Here is a comparison of the wood I split with my Mora and some found sticks, both thumb thick but the split wood is free of most bark and the drier wood in the center is exposed.
Light the tinder bundle. I used matches but it easy to use tinder/firesteel as well. You need to move fast in this step. Have half of the main fuel on the bottom (in the cone if you want).
As you lay the bundle on the fuel pile get ready to throw on the fine kindling so the initial flame-up of the bundle will be able to catch the fine kindling and in turn throw on the coarse kindling. Now the fire should be established- it happens pretty fast if done right. now its just a matter of adding kindling/fuel to keep it going.
Here are my scrambled eggs I cooked on the cone. I would normally cook twice as much but this is just a test.
Putting the fire out!
Time to get messy! Oh yes, you didn't think this would be that easy did you? This is probably the most important part. If you are cooking dinner and staying a while you can let the fire burn down to fine ashes, if you need or want to get moving its still possible. You need to be sure that the fire is out. This is how I do it.
First remove the cone exposing the ashes. Then dump water on the coals until they are cool enough to handle. Then I get my 2 qt pot full of water and I put all the ashes and coals in the pot and stir them around making sure they are all soaked and completely out.
Next you need to use your hands and get dirty clawing and digging around the wet dirt where the fire was. Its critical that you use your bare hands so you can feel the warmth of the earth where the fire was and be sure that there are no more coals or roots that can start a fire later when your gone. Move around the top layer of mud until its no longer very warm to the touch and you can be confident that its cool enough that their is no longer any possible fire hazard.
Now that the coals and ashes in the pot are cold and the ground where the fire was is wet and cool you can dump the pot on the fire spot and smooth it out.
Now you are done and can return the duff back were it was like no one was ever there and no one will ever know. Now go to bed with sweet and peaceful dreams.