Separate eggs. Stir the egg yolks, wine and flour until smooth, allow to swell for 15 minutes. Peel and wash the potatoes and cook in little boiling salted water for 20 minutes. Clean, wash and cut the beans diagonally into pieces.
Wash the savory. Put something aside for garnishing. Tie the remaining stems together and steam with the beans in a little boiling salted water for 12 to 15 minutes. Wash the lemon. Finely grate the skin of 1/2 fruit.
Peel the remaining half thinly and cut into fine strips. Squeeze 1/2 lemon. Peel garlic, crush finely and mix with yoghurt, lemon juice and grated lemon peel. Season to taste with salt and pepper.
Wash the maties, dab dry, cut in half and remove the tail. Heat the fat in a pot. Beat egg whites until stiff, fold into the batter. Pull fillets through the batter and fry four halves in hot fat for three minutes until golden brown.
Serve with drained beans and potatoes. Pour a little sauce over the fish. Serve garnished with lemon slices, grated lemon and savory.