1. 策划，谋划(阴谋等)
If someone cooks up a dishonest scheme, they plan it.

2. 捏造;编造
If someone cooks up an explanation or a story, they make it up.

3. 煮熟，烧熟，做好(尤指丰盛的饭菜)
If you cook up a quantity of food, especially a large quantity, you heat it until it is ready to be eaten.

1. make up something artificial or untrue

Synonym: fabricatemanufacturemake upinvent

2. prepare or cook by mixing ingredients

e.g. concoct a strange mixture

Synonym: concoct