During hot summers in Oklahoma City, Nancy Conley’s father would bring buckets of zucchini into the house. Conley remembers her mother cringing. “Not more zucchini?!”

Tomatoes and zucchini could survive and even thrive in 100-degree temperatures, Conley said.

One great thing that resulted from that overabundance of backyard zucchini was the dish that her family — the Hefners — called squash casserole.

In almost 45 years of marriage to real estate executive Herb Conley, the Diamond Head resident has made this a family staple at Thanksgiving, Christmas and many other times throughout the year.

“It’s a great way to camouflage vegetables for your kids,” the retired Contemporary Museum librarian says. “It doesn’t look like a vegetable.”

The casserole tastes rich, yet does not include cream or cheese. It is slightly sweet from sweet onion, a tablespoon of sugar and the secret ingredient — cornflakes.

The zucchini needs to be precooked and cooled. If not, the hot squash will quickly turn beaten eggs into scrambled eggs when they come in contact with the hot squash.

The dish is relatively easy to assemble. The cornflakes come pre-crushed — find them next to bread crumbs at the supermarket. To save a bit, buy cornflakes (not sugar-coated) and crush them yourself. The flakes add a specific taste both within the casserole and as a crunchy topping.

You could substitute breadcrumbs or panko flakes, but the taste and texture will be different.

Take care to fold in the cooked zucchini with the flakes, onion, butter, sugar and salt mixture so the squash holds it shape. When you serve it, the green skin of the zucchini mixed with the other ingredients creates an attractive layered look.

It’s a great recipe to make ahead of time since you can precook the zucchini and refrigerate it, or assemble the entire casserole and chill it until you want to bake it.

Conley says her mother tried the casserole with yellow crookneck squash, but that “didn’t take.” So green zucchini became the tradition.

You know that it is a special dish as both of the Conley children — Shawn, a professional bass player, and medical student Liz — now with families of their own, have called to request instructions for making it.

Hefner-Conley Family Squash Casserole

• Vegetable oil spray or vegetable oil to coat dish
• 3 pounds (about 8) zucchini squash
• 1/2 cup cornflake crumbs, or finely crushed cornflakes
• 1/2 cup chopped sweet onion
• 2 eggs, beaten
• 1/4 cup salted butter, melted
• 1 tablespoon sugar
• 1 teaspoon salt
• 1/2 teaspoon pepper (optional)
• >> Topping:
• 1/4 cup cornflake crumbs, or finely crushed cornflakes
• 1/4 cup salted butter, melted

Wash squash. Cut off and discard ends. Cut into 1/2-inch round slices. Cook in boiling water 8 to 10 minutes until squash is tender, but still holds its shape. Drain and cool about 1 hour. (Squash may be cooked the night before and refrigerated overnight.)

Heat oven to 375 degrees. Spray casserole dish with vegetable oil.

In a large bowl, combine squash and cornflake crumbs, then add onions, beaten eggs, melted butter, sugar, salt and pepper, if using. Gently fold ingredients so you do not smash squash. Pour into prepared dish. (Casserole may be refrigerated at this point and baked later.)

Just before baking, add topping: Sprinkle casserole with cornflake crumbs, then pour melted butter over top. Bake 50 to 60 minutes, until casserole is puffed and top is browned. Serve hot, at room temperature or cold. Serves 6 to 8 as a side dish.

Approximate nutritional information per serving, (based on 6 servings): 240 calories, 18 g total fat, 10 g saturated fat, 105 mg cholesterol, 600 mg sodium, 17 g carbohydrate, 2 g fiber, 8 g sugar, 6 g protein.

Lynette Lo Tom, author of “The Chinese Kitchen,” is fascinated by old-fashioned foods. Contact her at 275-3004 or via instagram at brightlightcookery. Nutritional analysis by Joannie Dobbs, Ph.D., C.N.S.