Step 1

Heat the oven to 180°C/160°C fan/gas To make the base, put the hazelnuts on a baking sheet and toast in the oven for 15 minutes or until golden, then set aside to cool. Put the biscuits and cooled nuts in a food processor with a pinch of salt and whizz to the size of breadcrumbs. With the motor running, slowly pour in the melted butter until combined. Using a metal spoon, press the mixture firmly into the prepared tin and up the sides, then chill.

Step 2

Meanwhile, for the praline, put the 100g hazelnuts in a heavy-based saucepan over a medium-high heat and toast until golden. Add the caster sugar and leave it to melt (don’t stir the sugar or it will crystallise).

Step 3

Line a baking sheet with non-stick baking paper. When the melted sugar is the colour of golden syrup, swirl the pan until all the nuts are coated, then tip onto the lined baking sheet and leave to cool completely. Chop into roughly 1cm pieces or roughly whizz in a food processor, then set aside.

Step 4

For the ganache filling, put the chocolate, double cream and sugar in a large heatproof bowl set over a pan of barely simmering water (don’t let the water touch the base of the bowl). Stir the mixture every now and then until the chocolate has melted and the sugar has dissolved. Remove from the heat and mix in the Frangelico. Whisk in a splash of cold water if the mixture looks greasy or splits – it will come back together.

Step 5

To assemble the tart, scatter a third of the praline over the chilled base, then pour over the ganache filling. Gently tap the tart on the work surface to release any bubbles and tip the tart case to fill to the edges, if necessary. Chill for 1-2 hours until set.

Step 6

Scatter over the remaining praline and serve with a dollop of crème fraîche and a glass of Frangelico, if you like.