Be sure the butter is cold and make sure not to overwork the dough.
1. Preheat the oven to 175°C on Convection Mode with a rack set on position 3.
2. Whisk together all the dry ingredients and the thyme.
3. Mix the butter into the dry ingredients by hand until hazelnut size pieces are formed.
4. Add in cheese and then the heavy cream.
5. Mix gently by hand until the dough comes together. This can also be done in a stand mixer or food processor, though caution must be taken not to overwork the dough.
6. Turn out the dough onto a floured surface and press out into a 178 mm disk, about 25 mm thick.
7. Cut disk into eight pieces.
8. Place on a parchment lined baking pan and bake for 16–18 minutes until golden brown around the edges.