Make the cake base.
Preheat the oven to 160 °C/ 325 °F.
Line an 8 x 8 inch pan with parchment paper or use a silicon pan like this one.
If you use a 9-inch pan, you can cut the cake in up to 16 pieces.
In a bowl, using a hand whisk, mix the wet ingredients for the cake base: eggs, egg whites, coconut oil, coconut milk, ...
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and lime zest.
Add a teaspoon of the lime zest to the cake base and keep the rest for the curd and topping.
In another a large bowl, mix all the dry ingredients for the cake base: almond flour, coconut flour, protein powder, Erythritol, baking soda, cream of tartar and salt.
Then pour in the wet ingredients for the cake base and mix until well combined.
I used a mixer but you can use a hand whisk too.
Bake for 30-35 minutes or until the top is light golden and the cake base is set.
Remove the cake from the oven and let it cool down on a cooling rack.
I left mine bake for 2 minutes more than I should have and the top almost burnt.
Make sure this doesn't happen to you and keep an eye on the cake.
Gluten-free flours get burnt easily.
Meanwhile, make the lime curd.
Juice the limes.
Place the egg yolks in a bowl.
Don't waste the egg whites and use them in other recipes.
You can find tips on how to use leftover egg whites in this post: Keto Lemon Curd.
Mix the egg yolks with the lime juice and add a tablespoon of lime zest.
Place the bowl over a saucepan filled with simmering water and stir constantly; make sure the water doesnt touch the bottom of the bowl.
Keep stirring for 8-10 minutes or until the custard starts to thicken.
Then take off the heat.
Add the butter and mix until dissolved.
If using matcha, spirulina or chlorella, mix it in the lemon juice before combining with the egg yolks.
Add homemade Keto Condensed Milk and mix until well combined.
Using the handle of a wooden spoon, poke several holes all over the cake base.
Pour the curd all over the cake base until covered and the holes are filled.
Place in the fridge to set for at least an hour.
Make the cream topping.
When the cake is ready, whip up the cream (or coconut milk) with Erythritol (optional) until you get firm peaks.
Spread all over the cake ...
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and sprinkle with freshly grated lime zest.
Store in the fridge for up to 5 days.
Enjoy!