Preheat oven to 350°F (180°C).
Place the whole blanched almonds (see notes) in the bowl of a food processor. You can also use the same weight in pre-blanched slivered almonds or - even easier - pre-ground almond flour/meal.
Pulse the nuts until they are uniformly cut into small pieces, then process until they have the texture of sand. If you use pre-ground flour/meal, it already has this consistency.
Add the sugar to the processor and continue to pulse until very fine in texture.
The sugar will help in grinding the almonds even finer. Pour the almonds and sugar into a large mixing bowl.
Add flour and whisk to blend.
Make a well in the centre and add the eggs and orange blossom water.
Whisk the eggs and orange blossom water into a paste. As you whisk, the liquids will gather some of the dry ingredients to make a thick paste.
Then, using a large wooden spoon, continue mixing the dry ingredients into the wet ingredients.
Eventually, you will need to give up the spoon and use your hands.
Pour the dough out onto a floured board and knead it to create a homogeneous dough – just a minute or two.
Flatten the dough into a long oval.
Coarsely chop the remaining 50 grams of whole almonds and sprinkle the nuts on the dough.
Fold or roll the dough to encase the nuts (it doesn't matter how you do this!) and knead the dough a few more items to distribute the nuts.
Depending on the size of your eggs, the dough may be a little sticky.
Pull the dough into a ball, flatten it, then divide it equally into six pieces.
If the dough is sticky, dust each piece liberally with flour.
Then, roll the pieces of dough into cylinders, 6 inches (15 cm) long and 1 1/4-inches (4 cm) thick.
Add more flour, if necessary.
Line two baking sheets with parchment and place 3 cylinders on each sheet of parchment.
Flatten each cylinder gently with the palm of your hand.
You want the end view to be an oval.
Brush the tops of the cylinders with the egg yolk and water mixture.
Bake in the preheated oven for 38 minutes (they should be quite golden), then transfer to a cutting board.
While still warm, cut them into 3/8-inch (1 cm) slices and return them to the baking sheet, standing up with space between each cookie.
Place them in the oven for 5 minutes to crisp the cut sides.