This keto adaptation of a Spanish Tarta de Santiago stays close to the original replacing sugar with low carb sweeteners. The classic version is traditionally dusted with icing sugar and decorated with the St. James Cross. You can use a stencil to decorate your cake or keep it plain. Xylitol has been used in this recipe however this can be swapped for erythritol.
Preheat the oven to 360 degrees Fahrenheit and line and grease an 18cm cake tin.
Add the xylitol to a food processor and blend to a fine powder. Transfer to a bowl and set aside.
Add the ground almonds, lemon zest, cinnamon and ½ cup of the powdered xylitol to a food processor. Pulse to combine.
Add the eggs and almond extract to the food processor and blend for a few minutes until you have a smooth and airy batter.
Carefully pour the cake batter into the greased cake tin and transfer to the oven to bake for 30-35 minutes until golden brown all over, cooked through and the sponge is coming away from the sides of the tin. Leave the sponge to cool completely in its tin.
Once the sponge is cool, you can place a stencil (if using) in the center of the cake and sift over the remaining powdered xylitol.