In a heavy-bottomed saucepan, combine the sugar and water and cook over medium heat, stirring constantly, until the sugar dissolves.
Add the toasted hazelnuts to the melted sugar and stir quickly to combine. As you put the hazelnuts, the mixture will start to crystalize due to the temperature changes.
But continue mixing as the sugar will eventually melt again. Turn off the heat when you start to see browning. Keep mixing and it will become shiny and light amber color.
Pour the mixture onto the prepared baking sheet and spread it out evenly.
Let the praline cool and harden for about 30 minutes.
Once the mixture has cooled, break it into pieces by placing it in a ziplock bag, whack it a few times using a rolling pin. Place it in a food processor.
Pulse the mixture until it forms a smooth paste. You may need to stop and scrape down the sides of the food processor a few times to ensure it's all blended.
Start adding neutral oil once you see that the mixture is coarse.
Keep pulsing until it becomes smooth and runny without any large bits from the nuts and caramel.
Transfer the hazelnut praline paste to an airtight container and store it in the refrigerator for up to 6 months!