Chocolate, hazelnut & candied lemon tart

1. For the base, crush the rusks to a fine crumb in a bowl and add the melted butter, mixing well. For every 100g of fine rusk, add 50g of melted butter. 
2. Press into the base of a 22 cm springform cake tin and 3 1/2 ½cm up the sides. Place in the fridge to cool.
3. For the candied lemon, cover the lemon peel strips with cold water in a pan and bring to the boil.
4. Boil for a few minutes then drain and repeat the process 3 times. The peel should be tender when pierced with a knife. If still firm, blanch again.
5. Place the sugar and water in a saucepan and bring to the boil. Cook without stirring until the sugar is fully dissolved.
6. Once dissolved, add the blanched lemon peel and simmer on a low heat for 10 minutes until well coated.
7. Carefully remove the peel from the syrup, coat with the castor sugar and place on non-stick baking paper to dry.
8. For the filling, place the chopped chocolate in a large heatproof bowl.
9. Warm the cream and pour it over the chocolate. Leave for 5 minutes, then whisk to melt the chocolate and create a smooth sauce.
10. Place 150 g of whole hazelnuts on the biscuit base and carefully pour over the chocolate sauce. Tilt the tin if necessary to ensure the chocolate goes to the edges.
11. Chill in the fridge for approximately 10 minutes,
12. When starting to set, sprinkle the chocolate evenly with the candied lemon and the remaining 50 g of chopped hazelnuts.
13. Chill until firm, then cut into wedges and serve.

SUGGESTION
Blanching the lemon peel and pith several times helps remove the bitterness of the pith. If the chocolate mixture splits, bring it together again using a hand blender.