Crushed chillies are medium in heat. They are produced by crushing small dry red chillies - only the flesh and the seeds are used. Chilli seeds are not actually that spicy. When a recipe suggests removing the insides of a chilli, it is because the light coloured pith (the bit that holds the chilli seeds together) is the part that is most hot.
Using Crushed Chillies
Chilli flakes can be sprinkled onto food as you would do with salt & pepper or they can be added to simmering dishes. When using crushed chillies, you can be as liberal in adding them as you feel. Of course the more you add to a dish, the more intense the heat.
Suggestions for chilli flakes include:
Curries, stir fry, seafood dishes, chilli con carne, paella, meat rubs, marinades, frying pastes, spicy salad dressings. Or sprinkled onto vegetables, oven bakes, grilled food, mixed into breads or on top of melted cheese - the list goes on!