In Epi's 3-Ingredient Recipes series, we show you how to make great food with just three ingredients (plus staples like oil, salt, and pepper). This naturally gluten-free cake is impressive enough for special occasions but secretly easy enough to make in less than an hour.

1 cup (2 sticks) unsalted butter, plus more for pan

8 large eggs

16 ounces semisweet chocolate chips

1/4 teaspoon fine sea salt

A 10"-diameter springform pan

Preparation Preheat oven to 350°F. Grease springform pan with butter and line bottom with parchment. Using an electric mixer on high speed, beat eggs in a large bowl until doubled in size, about 5 minutes. Place chocolate chips, salt, and 1 cup butter in a large microwave-proof bowl. Microwave on high in 10-second bursts, stirring between bursts, until smooth and pourable. Using a rubber spatula, gently fold one-third of the whipped eggs into chocolate mixture until incorporated. Fold egg and chocolate mixture back into remaining whipped eggs until incorporated. Transfer to prepared pan; cover bottom and sides of pan completely with foil. Set springform pan inside a large roasting pan; add hot water to a depth of about 1". Bake cake until a toothpick inserted into the center comes out clean and sides of cake begin to pull away from pan, 30–40 minutes. Let cool before serving.