Spread almonds in a single layer on a backing sheet and toast at 375° 5-8 minutes, until they are golden brown. Watch carefully so they don't burn.
Allow almonds to cool. Combine the 2 flours and mix in almonds once cooled.
Cream the butter with a mixer until it is soft and creamy. Add the salt and icing sugar and mix on medium low about 5 minutes, scraping down sides of bowl regularly. The dough will go from crumbly to a thick creamy paste almost like butter cream frosting.
Reduce the mixer speed to low and add the egg. Mix in the flour but stop mixing as soon as the dough comes together. Stir the almonds in until evenly distributed.
Lay out a large sheet of plastic wrap. Transfer the dough to the plastic wrap and shape in to an 8" X 4" rectangle about 1 ½ " thick. Wrap the dough up tightly and refrigerate until firm (about 3 hours).
When ready to bake, preheat the oven to 350° on regular bake setting (NOT convection).
Line baking sheets with parchment paper or silicone mats. Transfer sliced cookies to the baking sheet.
When firm, cut the dough in to 3 1 ½" square logs. (If you want perfect squares you may have to trim the outer edges of the dough a bit.) If you want to freeze some cookie dough see Note 2 below. Slice each log in to ¼" slices.
Transfer cookies to the baking sheet ½" apart and bake 8-10 minutes until just lightly browned on the edges. If baking more than 1 tray at a time switch the trays mid way.
When cookies are done allow them to cool about 10 minutes on the baking sheet and then transfer to a wire cooling rack to finish cooling.
If you are reusing a baking sheet allow the sheet to cool before transferring raw cookies to the sheet.
Store in an airtight container for a week or freeze air tight up to 3 months.
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