This Nutella Flourless Cake is so soft and scrumptious, you won't even be able to tell it's gluten-free! It only requires 8 ingredients, resulting in a perfect chocolatey no-flour cake.
Preheat the oven to 350°F. Line a springform pan with parchment paper. Brush the bottom and sides of the pan all the way to the top.
Separate 6 large eggs into two bowls. Using a handheld mixer, whip the egg whites until they are frothy, about 2 minutes. Once the egg whites are frothy, turn the mixer up to a medium speed and gradually begin adding in the sugar in a slow, steady stream. Continue to whip until stiff peaks form.
In a large bowl, stir together the Nutella, oil, amaretto, water, egg yolks, and salt. Sift and mix in the espresso powder. Once fully combined, add about a third of the whipped egg whites. Gently fold the meringue into the cake batter with a rubber spatula until most of the streaks are gone. Continue to fold a third of the egg whites at a time until fully combined.
Gently pour the cake batter mixture into the springform pan. Smooth out the surface. Pop the cake into the oven and bake for about 30-33 minutes. The cake will rise several inches and the top will be crispy. Stick a toothpick into the center and look for it to come out clean to know when it's done.
Take the cake out of the oven. Remove the springform ring and allow the cake to cool for a bit. The cake will begin to fall and form cracks on the top.
Serve the cake warm with powdered sugar or a heaping scoop of ice cream.
Notes
Use a springform pan lined with parchment paper because the cake rises a bit before falling.
Fold the egg whites into the batter a little at a time to prevent it from deflating.