Separate the egg yolks from the whites. Whip the whites and add the cream tartar to let it stand in soft peaks.
In a bowl, combine the egg yolks, melted butter, lemon juice, and salt. Mix thoroughly then add almond flour, peanut flour (or coconut flour), baking powder, and French herbs (if using). Mix until getting a homogeneous consistency. This will be a heavy dough until adding the egg whites
Add 1/3 the egg whites to the dough and mix until obtaining a homogeneous mix.
Add the remaining egg whites and gently mix until everything is well incorporated. Be careful not to overmix because the bread can lose volume.
Oil the 8x4 size loaf pan with coconut oil or butter and pour the bread batter in. Bake for 30 minutes. Check the bread by inserting a toothpick to make sure that it is well cooked in the inside.
Allow to stand for at least half an hour and unmold. Enjoy it hot and buttered.
Notes
*Note: If you don't want to use peanut flour, you can swap 1/4 cup of peanut flour with 1/4 cup of almond flour. I haven't personally swapped it to test the outcome yet but I believe it won't affect the consistency that much since the amount isn't that significant compared to the rest of the base.