Place all the nuts in a food processor and pulse them until you get a nice ground texture. Don't overdo it to prevent the oil exertion.
Mix all the ground nuts together and add psyllium powder, salt/stevia and spices to this mixture.
Separate the egg yolks from the whites and leave the whites at room temperature. Beat the yolks with lemon zest and sour cream until you get a nice and creamy emulsion. Start adding the dry ingredients mixture spoon by spoon.
In another bowl, beat the egg whites (using an electric mixer) with apple cider vinegar until you get a firm meringue. Now, using a spatula, gently add the meringue, bit by bit, to the bread mixture. Try not to mix too much so that the bubbles in beaten egg whites don't break.
Preheat the oven to 160ºC (320ºF) and pour in the bread batter into a metallic bread pan. (grease it with some butter if your bread pan does not have a non-stick coating) Decorate with various crushed nuts and seeds on top. Bake the bread for 50 minutes and then leave it in the oven to cool down. Do not open the oven during the baking process. Serve as a bread or a cake, depending on your preferences.