If using hazelnuts: Preheat the oven to 350 degree F (177 degree C) and place the hazelnuts on a baking sheet.

Bake for about 15 minutes or until fragrant and the skins begin to flake.

Remove from oven and place a dish towel over the nuts.

Let the nuts sit for a few minutes and then rub the nuts in the towel briskly to remove the skins.

Let cool and then chop coarsely.

If using almonds, walnuts, pecans, and/or macadamia nuts: In a 350 degree F oven bake the nuts for about 8 - 10 minutes or until lightly brown and fragrant.

Let cool then chop coarsely.

Then in a heatproof bowl over a saucepan of simmering water, melt the butter and chocolate.

Meanwhile break the digestive cookies into small pieces (about 1/2 inch).

Once the butter and chocolate are melted, remove from heat and stir in the digestive cookies, along with their crumbs, and the chopped nuts.

Spread this mixture into a lightly buttered 8 inch tart or cake pan, cover, and refrigerate for several hours or until set.

Cut or break into slices.

Store in an airtight container in the refrigerator.