Method
Prep:30min  ›  Cook:1hr25min  ›  Ready in:1hr55min 

1. Preheat oven to 160 C / Gas 3. Grease a 25cmx36cm baking tin with butter.
2. Mix pecans, dark chocolate, 150g caster sugar and cinnamon in a bowl; set aside.
3. Trim filo pastry sheets to fit baking tin. Layer 8 sheets of filo in prepared baking tin, brushing each sheet with melted butter; sprinkle with 1/3 of the pecan-chocolate mixture. Spread butter on 4 more sheets of filo and layer on top; sprinkle with another 1/3 of pecan-chocolate mixture. Repeat layers with 4 more sheets of filo and remaining pecan-chocolate mixture. Pour any leftover butter over the top of the baklava.
4. Cut through the top few layers of filo lengthwise, leaving bottom layer intact, to create 4 long rows. Make evenly-spaced zigzag cuts along each row to create small triangles, again leaving bottom layer of filo intact.
5. Bake in preheated oven until filo pastry is golden brown and flaky, about 1 hour; immediately finish cutting through to bottom layer of baklava.
6. Bring orange juice, honey, water, 100g caster sugar and lemon juice to the boil in a saucepan; reduce heat to medium and simmer until thickened, about 20 minutes. Pour sauce over baklava.
7. Melt remaining 55g dark chocolate and 1 teaspoon butter in the top of a double boiler over simmering water, stirring frequently and scraping down the sides with a rubber spatula to avoid scorching. Drizzle chocolate over baklava. Cover and refrigerate until ready to serve.