Before you start cooking: Cook 1 medium potato and let it cool down. Peel the cooled potato and shred it on a hand grater with small holes.
Making yeast starter: Add 1 teaspoon granulated sugar to half of the 1 cup lukewarm milk, then sprinkle in 2 teaspoons active dry yeast. Stir the mixture and let it sit in a warm place for 10-15 minutes until it becomes bubbly.
Place 3 cups all-purpose flour combined with 1 teaspoons salt in a large bowl, add the activated yeast mixture, grated potato, 3 ½ Tablespoons sunflower oil and the rest of the warm milk. Use a wooden spoon and your hands, or a kitchen mixer with a dough hook attachment, to make a semi-tough dough.
Allow the dough to rise in a warm environment until it doubles in size, which should take about 1 to 1 ½ hours.
Flour a worktop, dump the proofed dough on it, and divide into 6 equal-sized pieces. Shape them into balls and let them rise for another 15 minutes.
Heat the oil in a frying pan over medium heat (350 °F). To fry the Langoš properly, you need at least a 1 ½-inch layer of oil, so they can float while frying.
Use your fingers to stretch each piece of dough into a thin disc about 10 inches (25 cm) in diameter.
Fry until golden brown, then use heat-proof tongs to flip and fry the other side. It cooks quickly, taking about 1 - 1 ½ minute per side.
Make the garlic topping: Peel 3 cloves garlic and press them. Add the pressed garlic to a small bowl, combine with ¼ cup water and 1 teaspoon salt. Stir well.
Brush the top of Langoš with garlic topping and serve warm.