1 Grease six 6-ounce souffle dishes or custard cups. Place shredded zucchini in a colander; sprinkle with salt and toss lightly. Let stand
30 minutes. Rinse and drain. Squeeze out excess liquid. Set aside.
2 In a medium saucepan melt the margarine or butter. Stir in flour and dry mustard. Add milk. Cook and stir until thickened and bubbly. Remove from heat. Stir in the zucchini, feta cheese, and Parmesan cheese. In a large mixing bowl beat egg yolks with a fork. Gradually stir in zucchini mixture.
3 In a mixing bowl beat egg whites with an electric mixer on high speed until stiff peaks form (tips stand straight). Fold half of the beaten egg whites into the zucchini mixture. Gently fold remaining whites into zucchini mixture. Spoon into prepared souffle dishes or custard cups.
4 Bake in a 375° oven for 20 to 25 minutes or until a knife inserted near the center of each comes out clean.