Preheat oven to 220°C (200°C fan-forced). Lightly grease a baking tray and line with baking paper.
Place pastry on a lightly floured work surface and roll out just enough to cut a 26cm round. Place the pastry on prepared baking tray. Lightly score a border 2cm from the edge. Place in refrigerator for 20 minutes to chill.
Meanwhile finely slice potatoes to a thickness of approximately 2mm. Toss potatoes with 1 clove garlic, 2 teaspoons rosemary, olive oil, salt and pepper.
Remove pastry from refrigerator, brush border lightly with egg glaze.
In a small bowl combine goat curd, remaining garlic, rosemary and prosciutto, season with salt and pepper, mixing until well combined. Spread the goat curd mixture evenly over the centre of the pastry leaving a 2cm border.
Lay potato slices in rows around the pastry so each slice slightly overlaps, creating a concentric pattern.
Bake in preheated oven for 10 minutes, then reduce oven temperature to 200°C (180°C fan-forced), cook for a further 30-35 minutes or until the pastry is golden brown.
Note: This dish can be prepared in advance, re-heat at 160°C (140°C fan-forced) for 10-15 minutes prior to serving.