In a large bowl, combine the coconut flour, almond flour, baking powder, baking soda and salt. Stir very well to ensure everything is well combined.
In a separate small bowl, crack the eggs and whisk vigorously to add as much air as possible. Once the eggs are well whisked, add in the honey, olive oil and vanilla extract.
Combine the wet ingredients into the flour mixture, add lemon zest and whisk well to combine.
Slowly drizzle in lemon juice one tablespoon at a time, whisking thoroughly to add air.
Grease an 8.5″ x 4.5″ loaf pan with coconut oil. (Using a larger loaf pan will just mean you get a smaller rise on the loaf.) Once greased, use a spatula to transfer the batter to the pan ensuring the batter is evenly spread out.
Transfer the pan to the oven for 40-45 minutes until a toothpick comes out clean.
Allow loaf to cool in the pan for 15 minutes, then run a knife along the sides to help remove the loaf from the pan. Allow to cool further on wire rack if needed.