This probably isn't what you really want to hear, and it is gonna sound like I don't know what to tell you, so I am just rattling something off for the sake of posting, but it really is true, and your answer really is this simple.
You're just not eating enough. You may feel stuffed, you may think it is a lot of food, but it obviously is not above maintainence level for you, and you just need to eat MORE. Stay stuffed all day, take a weight gainer if need be, add olive oil to your shakes, just add more calories.
To be honest, a bowl of oatmeal and steak, egg, and cheese bagel is not enough food for a muscular 205lb guy who is looking to grow. Eat more, it's that simple. Anybody can gain bodyweight on any routine (or no routine at all), just eat more than you burn, if you aren't gaining, eat more, if you still aren't gaining, eat more. It can be a chore, but it is really the only answer.