In a mixing bowl, stir the yeast into the lukewarm milk, then add the malt syrup and a cup of flour. Stir, then add the salt and butter and stir again. Add 1 1/2 cups more flour and mix well. Knead on a floured surface or in the bowl for approximately five minutes.
Cover the bowl and let rise for about 90 minutes, or until doubled. The dough should have a soft, satiny feel to it.
Preheat the oven to 450° F, with a baking stone, if you have it, or a baking sheet, if you don't.
Lightly flour your cutting board or counter. Turn the dough onto your work surface and divide into 4 equal pieces; then cut each piece in half, so you have 8 total. Cover a baking sheet with a piece of parchment paper.
Roll each piece of dough out by putting it under your palms and moving your palms back and forth to make a long coil. The dough will stretch easily and then snap back. Alternate between pieces of dough so that each has time to briefly relax; it will stretch farther afterward. You want each coil to be about 24 inches long.
To shape the pretzels, take one end in each hand and twist them around each other a couple of inches from the ends of the coil. (You'll have what looks like a circle with a couple of antennae sticking up.) Lay the dough down on the parchment paper and fold the ends (the antennae) over so that they stick to the bottom of the circle—it should now look more or less like a pretzel. Prepare another sheet of parchment paper or a flour-dusted peel.
Meanwhile, boil 3 cups of water in a saucepan, then add the baking soda and stir to dissolve. With the water just below a simmer, pick up each pretzel with a spatula and hold it in the baking soda bath (on the spatula) for 20-30 seconds. It will puff up slightly and soften. When you remove the pretzel, let the baking soda water drain off the bottom (otherwise it will stick to the bottom and taste bitter), brush the top with the egg yolk and milk solution and then place on the new sheet of parchment paper or the peel. Sprinkle with salt.
You can either bake each pretzel immediately after boiling and brushing or you can wait and put them in the oven in a single batch. (I do the latter.) Bake for about 10 minutes; check in after 8 minutes. They are done when golden brown. Do not overbake; you want the contrast between the crusty outside and the pillowy inside. Eat as soon as they are cool enough to handle.