Line the baking trays with parchment paper and set aside.
Pre-heat the oven to 170°C/340°F (fan).
In a large bowl, beat together the butter, sugar, ground cardamom, nutmeg, almond extract and salt until pale and fluffy, about 5 minutes.
Add the ground almonds, semolina, flour, baking powder and baking soda. Use a rubber spatula fold everything together and form a thick and creamy mixture.
Scoop the cookies out into 20g portions and roll into rounds. Arrange the cookies on the baking sheets, leaving a 2cm gap between each one. Cover loosely with cling film and refrigerate for one hour, or up to 48 hours.
Top each cookie with a pinch of slivered almonds and/or pistachios, pressing them in gently.
Bake the cookies for 15 minutes and then remove from the oven. Cool on the oven trays for 15 minutes and then carefully transfer them to a wire rack to cool completely.
Store the cookies in an airtight container for up to 1 week. Keep them in a cool, dry place. Do not refrigerate.
You can also freeze the cookie dough for up to 6 months.
You may need to bake the cookies in batches depending on the size of your baking trays.