Homemade nacho chips with cheese sauce

Nacho chips

• 100 g Parmesan cheese, crust removed and cut into pieces (3 cm)
• 380 g polenta
• 220 g plain flour, plus extra for dusting
• 2 tsp sea salt
• 2 tsp baking powder
• 1 tsp mustard powder
• 1 tsp ground paprika
• 140 g olive oil
• 280 g full cream milk
• 1 tsp Worcestershire sauce

Hot cheese sauce

• 180 g cheddar cheese, cut into pieces (3 cm)
• 50 g salted butter
• 50 g plain flour
• 500 g full cream milk
• ½ tsp salt