Preheat the oven to 180°C/350°F/gas 4.
Make the pear mix. Place the pears, zest and juice of the lime, cardamom and agave nectar in a saucepan and bring to a medium-low heat. Stir occasionally for about 6-8 minutes to soften the pears. They should still retain some bite.
Make the topping. Whizz 2 tbsp of walnuts in a food processor (or alternatively, use a pestle and mortar) to grind. Mix together with the chopped walnuts, oats, sunflower seeds, coconut oil, agave and salt.
Place the pear mix in a ceramic ovenproof dish, followed by the topping. Place on a baking tray for 20-25 minutes, until warmed through and light golden brown on top. Finish off with toasted coconut flakes. Serve with low-fat crème fraiche.