In a medium saucepan, melt the butter. Once melted, stir in the brown sweetener replacement.Bring the mixture to a boil, and ensure the sweetener dissolves evenly.
In a large mixing bowl, whisk together the eggs, slightly cooled melted butter, almond milk, and vanilla extract. Whisk for about 3 minutes until the mixture is frothy.
Using oven mitts, carefully flip the pan and plate together, allowing the cake to settle onto the plate. Gently lift off the pan and remove the parchment paper.