Most wonderful zucchini dish

I remember as a child my mom made this dish as a light dinner and served it with salad. I am sure she made it at the height of zucchini season when it was summery and we would eat dinner at our picnic table in the yard. She stopped making it when we moved to a home with a yard too small to grow squash. I asked about it as an adult and she never told  me where the recipe came from which surprised me because I think the dish was always emptied when she made it. I finally rediscovered it in my mom's copy of The Jewish American Cookbook. They call it Zucchini with Cheese. In my version I used a blend of cheeses where their recipe called for American Cheese. I know my mom would not have used American Cheese but whatever good quality Cheese  she had on hand. I urge you to try this version.

 Cheesy Zucchini Casserole.............. 4 servings

3 small Zucchini
2/3 cup grated cheese (harvarti or sharp cheddar mix)
1/4 cup milk
1 egg well beaten
3 tablespoons butter

Preheat oven to 400°f
Grease a 10 inch square casserole dish. Wash and cut zucchini into slices 1/4 inch thick. Place slices in a large pan with just enough water to cover the bottom of the pan. Cook SQUASH until tender but not mushy. Remove from pan and place in casserole dish. Blend egg and  milk. Pour over Zucchini. Dot with butter and cover with grated cheese. Bake until cheese is melted and golden about 10-20 minutes.