Step 1

Preheat the oven to 325°F.

Step 2

Using a food processor or box grater, grate the zucchini. Place the grated zucchini on top of several layers of paper towels and wring dry. If necessary, repeat 1 to 2 times to remove any excess moisture.

Step 3

In a 10-inch cast iron or ovenproof nonstick skillet, melt the butter over medium heat. Add the shallot, zucchini, and ½ teaspoon salt; cook, stirring occasionally, until the moisture evaporates and the zucchini is tender, 7 to 8 minutes.

Step 4

Meanwhile, in a medium bowl, whisk together the eggs, heavy cream, a heaping ¼ teaspoon salt, and ¼ teaspoon pepper.

Step 5

Add the cooked zucchini and grated cheese to the egg mixture and stir to combine. Pour the frittata mixture into the pan (no need to wash it), then place in the oven and bake until set, 25 to 30 minutes. Immediately place a dish towel or oven mitt over the pan handle after you remove it from the oven; it's easy to forget that it's hot and burn your hand.

Step 6

Freezer-Friendly Instructions: The cooked frittata can be frozen for up to 3 months. Remove the frittata from the freezer about 24 hours prior to serving and reheat it in the microwave or, covered with foil, in a 300°F oven until hot in the center.