1. To make marmalade, place orange slices in a large saucepan. Cover with cold water. Bring to a gentle boil. Boil for 1 hour. Strain and reserve 125ml of the cooking liquid.

2. Remove and discard any pips from orange slices. Trim flesh and pith away from peel. Discard pith and purée flesh until smooth. Push purée through a sieve. Finely chop peel.

3. Place sugar, strained orange flesh purée, chopped peel and reserved cooking liquid in a large saucepan. Bring to a boil. Boil gently, stirring frequently, for about 20-25 minutes or until thickened and gel-like.

4. To make biscuit base, process flour, sugar, baking powder, salt and butter to form fine crumbs. Whisk yolks and extract until combined. Add to processor. Process until mixture just comes together. Form dough into a disc and cover with plastic wrap. Refrigerate for 30 minutes.

5. Preheat oven to 170C. Line an oven tray with baking paper.

6. Roll out dough on a lightly floured surface until ½ cm-thick. Using an 8cm round cutter, cut out 6 circles. Place on prepared tray. Bake for 15-20 minutes or until golden and crisp. Remove from oven and cool for 2 minutes on tray. While still warm trim biscuits to size using a 7.5cm presentation ring.

7. To make caramel sauce, place sugar in a small saucepan on medium heat. Stir constantly for 2-3 minutes until sugar melts. Slowly add juice, whisking until sugar dissolves. Cook over medium high heat for 5-6 minutes until mixture thickens. Cool completely.

8. To make cream filling, beat cream, mascarpone and sugar to form soft peaks. Fold in ¼ cup of the marmalade.

9. To assemble, line a tray with baking paper and lightly grease 6 presentation rings (7.5cm round x 6.5cm tall). Arrange a layer of orange segments over base of each ring, ensuring there are no gaps. Drizzle with a little caramel sauce. Spoon about 1/3 cup cream filling over orange segments. Spread each biscuit with 1 tbs marmalade and gently ease biscuit, marmalade-side down, on top of cream. Refrigerate for 1 hour.

10. Run a knife around edge of biscuit base to loosen. Place a board or tray on top of presentation rings and invert whole tray, so that tians are orange segment-side up. Remove baking paper. Leave for few minutes to let the weight of the tian help it slide down. If it does not slide all the way, run a thin tipped knife around inside edge of presentation ring and gently tap tians out.