Melt chocolate in a water bath or microwave. Add oil, gently stir until smooth, cool. In a separate bowl, beat the eggs with sugar in a light foam, add the sifted flour, mix.
Chop the nuts with a knife and brown lightly in a dry frying pan until golden brown. Mix chocolate and butter with dough, add whiskey and nuts.
Cover a rectangular shape about 20x25 cm in size with parchment, put the dough into it and carefully level it. Bake in an oven preheated to 180 ° C for about 40 minutes. It is very important not to overdry the brownies - they should remain slightly creamy inside.
It is better to cut brownies already cooled: they can crumble when hot. Serve with berries, whipped cream or a scoop of ice cream.