How to make
Beat the eggs well and add flour. To this mixture, add grated zucchini, chopped onion, finely chopped sausage, crumbled feta, half of the grated cheese, dill and salt and pepper to taste.
Pour the mixture into a greased baking dish. Beat mayonnaise and mustard and spread it on the top and smooth it out.
Add the tomato slices and sprinkle with the remaining grated cheese. Put the gratin with zucchini and sausage to bake in a moderately hot oven just at the bottom for 30 to 40 minutes.
Then turn the top on, until the cheese get a nice golden color.