Preheat your oven to 350°F and line a loaf pan with parchment paper.
In a large bowl, mix together almond flour, coconut flour, flaxseed, baking powder, and salt.
In another bowl, whisk the eggs, almond milk, olive oil, and apple cider vinegar until smooth.
Pour the wet mixture into the dry mixture and stir until a thick batter forms.
Transfer the batter into the prepared loaf pan and smooth the top with a spatula.
Bake for 45 to 50 minutes, or until a toothpick inserted in the center comes out clean.
Let the bread cool completely before slicing. Patience is hard, but it pays off.