Step 1

Preheat the oven to 350º.

Step 2

Butter and lightly grease a 10x4 inch loaf pan , or a 9-inch (24cm) springform pan.

Step 3

In a food processor, pulse the toasted hazelnuts with 2 Tbs of the granulated sugar until finely ground. Take care not to over grind the hazelnuts to the point where they become a nut butter, or the cake will be oily and heavy. Set the nut mixture aside.

Step 4

In the bowl of an electric mixer, or a large bowl with a wooden spoon, cream the butter until light, then add the remaining white and light brown sugars and cream the mixture until it is light, pale and fluffy.

Step 5

Add the eggs, one at a time, beating well after each addition, and scraping the sides of the bowl periodically. Don't worry if the mixture looks separated and broken; it will come together when you add the flour.

Step 6

Beat in the vanilla.

Step 7

Sift the flour, baking powder and salt together.

Step 8

Add the nuts and mix well to combine.

Step 9

Add this to the butter in three additions, alternating with the cream in two additions, beginning and ending with flour. Mix only until incorporated. Do not over mix.

Step 10

Add the hazelnut liqueur or the oil and mix well with a spatula.

Step 11

Scrape the butter into the prepared pan and bake for 1 hour and 10 minutes or 1 hour and 20 minutes, or until the top springs back when lightly touched and a tester inserted in center comes out clean.

Step 12

Transfer to a wire rack and cool 20 to 30 minutes. Run a thin bladed knife around the edge of the pan, remove the sides if using a springform or unmold if using a loaf pan.

Step 13

Cool on a rack completely before serving or wrapping or storing.

Step 14

This cake tastes better the second day and lasts up to 5 days.

Step 15

Spread hazelnuts in a shallow baking pan, single layer, and bake in a 350º oven, for about 7 to 10 minutes or until fragrant.

Step 16

Watch closely, as they burn easily, and shake pan several times. The skins will begin to crackle.

Step 17

Transfer the toasted nuts to a bowl lined with a clean kitchen towel, bundle the nuts in the towel and set aside just until they are cool enough to handle.

Step 18

Rub the nuts briskly, then open the bundle and use your fingers to rub the papery skins from the nuts.

Step 19

Don't worry if some of the nuts refuse to be totally skinned.

Step 20

Store in an airtight container.