Keto flan recipe. 1/3 of a cup of erythritol. 1 teaspoon of unsalted butter. 2 teaspoons of water. Heat until golden brown and bubbling, stirring constantly. 2 large whole eggs plus 2 extra egg yolks separated from the whites. 1 cup of heavy cream. 2 teaspoons of vanilla essence. 1/4 cup of erythritol. Hot water. Bake for 1 hour at 300 degrees Fahrenheit.