1. Preheat oven to 180°C. Grease and line two baking trays with baking paper.
2. Place butter and cheeses in the Stainless Steel Mixing Bowl. Using the scraper beater on medium speed (5-7) mix until well combined. Add eggs one at a time, making sure to beat well after each addition.
3. Reduce to low speed (1-4). Add flour and cayenne pepper mixing until well combined.
4. Use a rolling pin, roll out dough until ½ cm thick. Using a 4cm cutter cut dough and place onto prepared trays. Sprinkle with rock salt.
5. Bake for 10 minutes or until cooked. Place on wire rack to cool.