The making of lye baked goods requires the use of strongly corrosive liquids.
Therefore the treatment of the Brezels with lye needs to be done with caution. I recommend long sleeved clothes and gloves. The eyes should be protected from splashes with glasses. In addition, children have to be strictly kept away from the lye.
500 g all-purpose flour
1/4 l lukewarm water
1 pack dry yeast
50 g butter or plant oil, depending on taste
1 - 2 teaspoons of salt
Mix flour, yeast, fat and salt together. Add water stepwise and knead until a solid dough is formed (don't add to much water). Knead a dough with the ingredients, until it comes of the fingers easily. Let the dough stand at a warm place until it at least doubled in size (ca. 1 h). Knead again and leave standing for at least 10 min.
Knead the dough again on a flour-dusted surface, and half it with a knife. Cut the two halves in two again, and the remaing quarters into three pieces each. Roll the pieces to a round shape and leave them standing for at least 10 min.
On a flat surface, flour-dusted or greased, roll the dough pieces with both hands palm-down in parallel, whereby the hands are moving slowly apart to the outside. The middle bit should stay thicker and the end bits getting thinner to the outside. Roll to a lenght of ca. 40 - 50 cm (16 - 20 inches).
Lift both ends and bring them together at the front. Twist the two strings, so that they are slung together ca. 5 - 10 cm from the end (2 - 4 inches), so that the left end is on the left side again. Press the ends into the thicker bit.
It sounds more complicates than it actually is, but you just have to look at a Brezel and you know how it is meant to look. And with the dough you can start again and try as many times as you want.
Note: the lye is corroding Aluminium and Glass, therefore this should be done in a stainless stell pot or in plastic bowls (the latter one only for cold lye).
There are two possible variations for the lye: Sodium Carbonate solution or Sodium Hydroxide solution.
Sodium Carbonate has the advantage that it can be easily bought in supermarkets. You can also use Sodium Bicarbonate (Sodium Hydrogen Carbonate), which is forming Sodium Carbonate when heated. The disadvantage is that you need to boil the solution, which makes it more hazardous.
For this variaton a ca. 10% solution is used, meaning 100 g of Sodium (Bi)Carbonate is dissolved in 1 L of water. Bring the mixture to the boil, and dip the dough Brezel using a flat pan turner into the boiling lye. Press it under the surface or turn it, using no more than 10 sec, and put it on a baking tray that is lined with baking paper.
In contrast to the first variation, Sodium Hydroxide solution is used cold. But therefore it is not easy to get, at least in Germany. There are some specialised online shops that sell it to the general public, but I only know the German ones. If you are looking for it make sure it is "food grade" or "p.a.", as there is a lot of low-quality Sodium Hydroxide in the chemicals market which contains unwanted side products like heavy metals. Also I recommend to get pellets, as the powder draws moisture from the air quickly and then turns liquid.
Sodium Hydroxide is used as a ca. 3 % solution, meaning that you dissolve 30 g in 1 L of water. Always put the water in first and add the pellets while stirring, the solution gets slightly warm. Don't let the Sodium Hydroxide get into contact with skin!
Dip the dough Brezels into the cold lye for ca 30 sec, making sure they are submerged completely, and put it on a baking tray that is lined with baking paper.
Note: if your skin gets a splash of lye, rinse immediately with lots of water. Contact a doctor if necessary.
Before baking you can sprinkle the Brezels with coarse salt (I never do), and you can cut the thick bit lenghtwise to get a white back, like it is done in some local variations (in the Pfalz they don't tend to do this).
The Brezels are baked in the oven at 220°C normal or 200°C with air circulation. The baking time depends on size and thickness of the Brezel shape, but it should be around 15 - 20 min. You can easily follow it watching the colouring.
Brezels taste best when they are still warm. Lined with butter and accompanied with a cool wheat beer makes a combination that is hard to top!