Preheat the oven to 160C (320F) and line a baking sheet with greaseproof paper.

Grate the Parmigiano Reggiano.

Place a small heap of the cheese (about 1 tbsp) on the grease proof paper and shape into a vague circle.

Repeat until you have covered the baking tray. Make sure not to place the circles too close together as they will spread out as they melt.

Bake the cheese rounds until they start to change colour (about 5 minutes).

Remove the tray from the oven and, while they are still soft, mould them into cup shapes. Do this by peeling them off of the grease proof paper and place into mini muffin tins, pressing down firmly to create the shape. (If any of the Parmesan Crisps get too cool and crunchy you can re-warm the for a few seconds, back in the oven to make them pliable again).

Allow the cups to cool in the tin so that they crisp up into the correct shape.

Dice up the avocado and sun-dried tomatoes and season well.

Spoon into the Nacho Cups and top with half a teaspoon of sour cream.

Garnish with chilli or coriander leaves or anything that takes your fancy and serve.