First cook the lentils in salted water according to the instructions on the packet.
In the meantime, grate the zucchini with the coarse side of the grater and chop or squeeze the garlic.
Drain the lentils and mix with the lightly squeezed zucchini, egg and 1 - 3 tablespoons of flour until you have a thick, malleable mixture. Season with curry, salt and pepper and shape patties from the mixture.
Heat a little oil in a pan and fry the patties for about 3 minutes on each side. Then place on some kitchen paper to soak up the excess oil.
For the dip, mix the yoghurt with finely chopped mint and a little salt.
Serve the lentil patties with the dip and, if you like, with the crumbled feta cheese.