Roast hazelnuts in a baking tray at 180C/350F for about 10 minutes until toasted and aromatic and the skins turn a couple of shades darker.

Remove from oven and while the hazelnuts are still warm, rub between a towel or paper towel or your fingers to remove the skins. Aim to remove at least 70% of the skins (which can be quite bitter). If there are some stubborn ones, you can pop them back in the oven for a few more minutes and try again.

Let the hazelnuts cool completely – preferably overnight – or they will not blend as finely as they should (and will be hard work for your blender).

The next day, in a high-speed blender or food processor, blend hazelnuts until fine/buttery, then add all remaining ingredients and blend until smooth and creamy.

Combine all ingredients in a food processor and blend on low speed until well combined and a sticky 'dough' forms. If the mixture doesn't feel sticky enough to stay together, add another date and process again.

Take a spoonful at a time and press it into a muffin tray with your fingers. Be sure to make the shells thick enough on all sides so that they won't break when removed from the tray (just under half an inch thick is perfect).

Pop tray into the freezer and allow to freeze solid - an hour or two if you can wait that long.

Remove tray from freezer and gently lift shells out, using a knife to nudge them out from one side if you need to.

Use a piping bag to fill shells with Nutella.

Eat immediately or place in an airtight container and return to the freezer, removing them just before serving.