Preheat the oven to 350 degrees F and line a loaf pan with parchment paper.

In a small bowl, stir together the sugar-free sweetener and cinnamon for the cinnamon swirl mixture. Set aside until ready to use.

Whisk together the eggs, full-fat coconut milk, and vanilla extract in a large mixing bowl and mix until well-combined. You can also use a stand mixer or a hand mixer if you prefer. Note: If your coconut milk is separated (this happens when canned coconut milk is cold), heat it in the microwave for 20 to 40 seconds until it is nice and creamy.

In a separate bowl, whisk together the almond flour, coconut flour, sugar-free sweetener, baking powder, and sea salt.

Pour the flour mixture into the bowl with the wet ingredients and mix until combined into a thick batter.

Transfer half of the bread batter to the parchment-lined bread pan and spread it into an even layer.

Sprinkle the majority of the cinnamon-sugar mixture over the batter, leaving just 1 to 2 tablespoons for the top of the bread.

Pour the remaining batter on top and use a rubber spatula or a spoon to gently spread it over the top of the cinnamon and sugar layer. Sprinkle the remaining cinnamon mixture on top.

Use a butter knife to draw a large S shape down the length of the batter. Give the loaf pan a little shake to allow the batter to come back together.

Bake on the center rack of the preheated oven for 50 to 60 minutes (I do 50), or until the bread is golden brown and tests clean. Allow the bread to cool for at least 20 minutes before slicing and serving (if you can allow it to cool completely, it will be easier to cut).

To make the optional glaze, stir the sugar-free powdered sugar and water together in a bowl until it reaches your desired consistency. Drizzle over the bread, and enjoy!