Mix salt, flour, eggs, milk and melted butter to a smooth dough, rest 20 min. Finely chop onions and garlic and sauté in oil until translucent. Add frozen spinach and whipped cream, season with nutmeg, salt and pepper and defrost leisurely. Knead dough again and bake 8 pancakes in order.
Grease the gratin dish with oil, fill the pancakes with spinach and half of the cheese and place in the dish. Cut tomatoes into cubes and spread evenly over pancakes with sour whipped cream. Sprinkle remaining cheese and sesame seeds on top and bake at 180 °C for 20 minutes.
Our tip: Fresh chives are much more aromatic than dried ones!