To make the macadamia praline, preheat oven to 180°C. Place the macadamias on a large tray and roast in the oven for 10 minutes, or until golden. Set aside.
Place the sugar and water in a small saucepan and stir over low heat to dissolve the sugar. When the sugar has completely dissolved, increase heat and bring the mixture to the boil. Boil over high heat, swirling every now and then (but not using a spoon), until the mixture starts to turn golden. Watch carefully and remove immediately when the mixture turns a dark golden colour.
Carefully remove from heat and pour over the roasted macadamias, covering them all with the toffee. Allow to cool and set completely.
When completely set, place a tea towel on a bench with a layer of baking paper over it. Lay the toffee piece on the baking paper and cover with another sheet of baking paper and another tea towel. Use a rolling pin to smash down the toffee to crush it. You can leave it as big shards or smash it a little further to finer shards. Store in an airtight container until ready to use.
Spread the crème fraiche and figs on a plate and sprinkle generously with the macadamia praline. Serve immediately.