Take milk, yogurt and salt into your yogurt bowl and mix it with a spoon.
Then sift the flour and knead it until the dough is gathered. It should have a soft, light consistency that sticks to your hand. Since you will use flour while opening the pieces, be careful not to use the flour too much while kneading.
Cover the dough you kneaded with a clean cloth and set aside for 45 minutes.
I do not give the preparation of the inner filling in detail. But I must say this; I definitely recommend preparing the spinach raw, it becomes tastier. Add onion, oil and spices, mix and prepare.
Cut tiny tangerine-sized pieces from your dough, which has rested for 45 minutes, and roll it out on the lightly floured counter with the help of a roller.
Add the filling inside and press the edges with your fingertips.
Put a large pan on the stove. Bake your boreks until the top and bottom is browned.
Never add oil while cooking.
Then, if you wish, when the boreks are cooked, you can lightly grease them with butter.