Preparation for the pastry
To use a food processor
Pulse the flour, sugar, and salt to combine. Add the butter pieces, and pulse until the mixture looks like coarse meal with some pea-size pieces. Sprinkle slowly with the water, and pulse until the dough just comes together.
To work by hand
In a large bowl, whisk the flour, sugar, and salt. Using a pastry cutter or your fingertips, work the butter into the mixture until most of it resembles coarse meal with some pea-size pieces. Form a well in the centre. Sprinkle with the ice water. Mix with your fingertips until the dough holds together enough to form a ball. If too dry, add the remaining water by the teaspoon, and mix until the dough comes together.
For both methods
Form the dough into a ball, put it between two sheets of plastic wrap, and then press it into an 8-inch round. Wrap it tightly in plastic wrap and refrigerate for at least 1 hour or up to 2 days before rolling out.
Preparation for the Star Anise Poached Guava
Peel and quarter the guavas.
Put in saucepan and just cover with water.
Add sugar and star anise.
Bring to a gentle boil then turn down and simmer for 10 minutes or until flesh is soft but not mushy. Allow to cool in the syrup.
Mint Sugar
In a food processor, spice grinder or coffee grinder, blitz 1/4 cup packed fresh mint leaves and 1/2 cup caster sugar until well combined.
Galette Assembly
Heat oven to 200°C. Cut the dough into 8 equal pieces and roll into 5mm thick circles. There’s no need for neat edges, it’s a rustic dish! Place the circles on an oven tray lined with baking paper.
Cut one of the guava quarters into 5mm slices and arrange in the centre of a pastry circle leaving a 3cm border. Now fold the border up over the fruit. There should be a large hole over the fruit so any steam can escape.
Before baking, dot the galette with cold butter, brush the crust with an egg wash or the reduced poaching liquid and sprinkle with mint sugar
The galette should bake until the crust is a deep golden-brown and the fruit is bubbly and cooked. This usually takes about 30 minutes or so. Transfer the galette, parchment and all, to a wire rack and let it cool before serving.