Cut the pastry sheets in the half. Put two half sheets the one over the other. Add in the center a feta cheese square. Close it like an envelope and leave aside. Do the same with all feta cheese pieces.
In a small pot, add the honey, the vinegar and 2 tablespoons of water, boil and stir. Heat well the oil and fry the "packets" of cheese both sides until golden brown.
Transfer the feta cheese pastry packets to a platter lined with paper towels to absorb any excess oil. Pour each one with 1-2 tablespoons honey sauce and sprinkle with sesame seeds.