I am going to pour the first floor of my house first then stack and pour the garage.  In my design, the garage is attached to the main house via a breezeway.   This breezeway is built with 90 degree corner forms and composes the first pour for the house.  

What is the best way to tie in the garage ICF structure to the house since I will be pouring the garage later?  Should I pour the breezeway walls first, then puncture the corner blocks with rebar?  Should I puncture the forms now with rebar and foam the joints in the corner before pouring?   I guess I am a bit concerned about the weight of concrete ripping the rebar out.  And in general, since this is my first pour, I am hesitant with messing with the corners in general.

Since the foundations for both the garage and house were poured at the same time, is there another way to tie them together? 

Matd
I'm a little confused about your explanation? The foundation is already poured as a conventional footing and wall, correct? So your ICF walls will sit on the full-size concrete foundation walls?
I think I wouls do the house without the breezeway, and then tie everything together that way.
I don't understand the concrete ripping out the rebar?
Messing with corners? Please explain a little more what you are doing...and once again, where is your tech help. Which block, Where are you?

Hopefully, this diagram will help.

The purple represents what I already have stacked (the breezeway).  The red is where I need to tie the garage into the breezeway (currently not stacked).  I don't have enough bracing to pour both at the same time.

The foundation for the house and garage was ICF block also.  

Mat If I understand what you are dealing with there are two issues.
1. Attaching the garage foundation ICF to the house foundation ICF at a later date. Here is how we did this back when we where new at this, and in our case could not afford the extra bracing. We would extend the rebar that was in our wall out of the foam 2' and pour the first wall. You will not have a mono on this when you pour the next wall to it but at least you will have concrete up against concrete, (oh by the way when the first one cures we would cut the foam away before setting the next wall). Shear issues are very minimal this way, the bigger issue will be getting the joint sealed so you do not get moisture penetration.
2. Check out a rental store for bracing or a construction supply house some of them have bracing to rent and it will save you the cost of a pumper truck and extra labor if you can pour this all at once plus the garage foundation will be monolith with the house and breezeway.
Had you not already stacked the house foundation this wall would have been better being a straight wall and doing a T-Wall where the breezeway meets the garage, at least the way it looks in the drawing.