This is the continuation of my accounts of making desem bread , which is made with just flour, water, salt and nothing else. It's somewhere between regular baking and a science project.
Time to start the desem now. The ingredients for today:
The only piece of equipment needed for this process (besides a mixing bowl) is a container that can hold a good amount of flour, that can be used as an incubator for the desem. The book  says any container will do as long as the desem ball will be surrounded on all sides by 3-4 inches (say about 8-10 cm) of flour. I use a largish stainless steel stock pot. (The book suggests a strong paper bag as one option, but growing a pet in a paper bag just seems plain wrong.)
I prepared the incubator by washing out and carefully wiping the pot - it was clean anyway, but just in case. I then filled it about half full of flour.
Then, in a bowl I mixed 2 cups of flour, with 1/2 cup of bottled water. Now, as any baker knows the amount of water you need to add to flour on any given day varies wildly. When it's dry, you need more, and when it's raining, you need less. Today it's been rather dry, so I needed to add 1/4 cup more. The dough is rather stiff, but still yielding - stiffer than regular bread dough but not rock hard either. I knead it for a few minutes. No need to really work it at this point.
Here's a picture of the dough ball. It's about 11cm/ about 4.5 inches in diameter.
Now to buy the desem ball in the flour. I put it in the center of the pot, and fill the pot up with flour. I pat down the top of the flour and form an X, as you see here:
The lid goes on to protect the contents from dust and crawling things.
Now to put the pot in an appropriate place. The key here is temperature. The natural leavening agents that will make the desem what it is, seem to grow at a cool yet not freezing temperature. If it's too warm, the desem may turn sour or just plain bad, and if it's too cold it will just sit there. The book says the temperature should be 50°F and 65°F, or 10°C to 18°C. That's a surprisingly difficult temperature to achieve in modern life, especially if you live in an apartment. The only thing you can do is to go around and measure the ambient temperature at various spots. Luckily, we live in a house where not all the rooms are heated. So the incubator/pot goes in the semi-basement where the washing machine lives.
I'll let the dough sit for 2 days before checking it. Grow, little desem.