In a clean jar with lid, mix 2 cups chopped hazelnuts, 1 cup vodka and ½ cup cognac. Close tightly, place in a cool, dark place (like a kitchen cabinet), and let steep for 4 weeks.

After that time, the mixture with be cloudy. Scrape 1 vanilla bean and add all of it, seeds and pod, to the hazelnuts and let steep 2 more weeks.

Make a simple syrup by placing ½ cup sugar with ½ cup water in a saucepan. Bring it to a boil and remove from the heat. Let cool.

Have ready a colander and piece of cheesecloth. I use the drip coffee filters. Sieve the hazelnut mixture through it, letting it drip. Don't rush it. Discard the filters as they fill with the wet hazelnut powder. Your liquid will be clear, and you'll have most of your hazelnuts intact.

Once the whole of the liquid is sieved, you can either throw away the hazelnuts, or process them and put them back in the original jar. Or use them for the hazelnut brownies (I highly recommend it).

Add half of the simple syrup to the liqueur. Taste it. It will not be completely mellow but you will get a feeling if you want more sweetness. Add more of the syrup if you feel it needs it.

Transfer to a bottle, using a funnel, add the remaining scraped vanilla bean, close the bottle and keep with your other liqueurs.