You probably gotta give folks here a bit more stats to get some help. Like age, height, current weight, what is your training like, etc.
Sounds to me like your wanting to go up to 185 and mentioned 20lbs so your now 165? Can't really gauge without knowing all the other stuff. But keep it simple. ... to increase weight = more food. Take what you currently eat and add more. A little at a time to see how you react. Don't want to increase calories too much and just get fat.