2) Spray 8 small tea cups or souffle dishes with nonstick spray. Place on a baking sheet.
3) Heat the chocolate and butter together in a large glass bowl resting over a saucepan of simmering water, until the butter and chocolate are melted, stirring with a wire whik untilsmooth.
4) Stir in the sugar and mix well.
5) Add the eggs, one at a time, beating well, so that the eggs do not cook.
6) Stir in hazelnut extract and flour.
7) Divide batter evenly among prepared moulds, filling 3/4 full.
5) Bake for 12 to 14 minutes, or until sides are firm but centres are soft. Leave to stand 1 minute.
6) Turn the cakes out into dessert dishes. Top each lava cake with a little hazelnut liqueur and a spoonful of nutella. Serve immediately, with a scoop of vanilla ice cream and chocolate shavings.