For the cheese straws:
1 egg
1 tbsp milk
375g (12oz) pack ready-rolled puff pastry
50g (2oz) Parmesan, finely grated
100g (3½oz) Gruyère, finely grated
For the dip:
1 large ripe avocado
2 tbsp mayonnaise
1 tbsp chopped fresh coriander
1 tomato, roughly chopped
2 tbsp sweet chilli sauce