Dissolve the fresh yeast in the lukewarm water. If you are using dry instant yeast, mix it with the flour.
Mix and knead: Mix the flour, salt, and sugar in a large bowl. Add the yeast water to the flour, add the oil and mix well with a wooden spoon. When the dough is well mixed, start kneading it until it is smooth and no longer sticks to the bowl.You can knead the dough in a stand mixer. Place the flour, salt, and sugar in the stand mixer, add the yeast water and knead for about 2-3 minutes until the dough is smooth and doesn't stick to the bowl's walls anymore. Let rise: Transfer the dough into a bowl, cover with a clean towel and let rise in a warm place until doubled in size, about 40 minutes or until doubled in size.
Divide dough: Place the risen dough on the very lightly oiled working surface. Knead shortly and divide the dough into 8 equal parts. Form 8 balls.
Form langos: Take one ball and start pressing and stretching it on the working surface to form a circle of about 15 cm/ 6 inches with lightly oiled hands. You will not need a rolling pin; press the dough with your hands and fingers.
Heat oil: Heat enough oil in a wok or deep frying pan so that the langos can swim. Make sure the oil is hot enough before you start frying your first langos. To check that carefully, insert a toothpick in the oil; if you see tiny bubbles forming around it, then you will know that the oil is hot enough.
Fry langos: Fry one langos at a time, as they are pretty large and should have enough place in the pan.Carefully place one langos to the oil. Fry it for about 2-3 minutes on each side or until deeply golden. Take it out with a slotted spoon and place it on paper towels to absorb the fat. Pat dry on the other side with an extra paper towel.