I have been looking at doing the cathedral windows quilt for a while now. I am thinking of doing it a few different ways. I had thought of the 10 min block also. but would have to find the best fabric for putting in the center of the quilt. I think that I might make a small pillow to go with the baby quilt. this one in just the normal cathedral pattern. I am still trying to figure out the amount of fabric to get it to the right size.

Here's a chart to figure out the sizes to cut. It only goes up to a 4" window size but it might give you an idea.
http://ajpadilla.com/tutorials/cathe...utting-squares

thank you thank you thank you thank you thank you!!!!! this is actually perfect. I will now be able to cut the center blocks perfectly. thank you so much.

I've seen them done with batting cut to fit under the 'window'; but, generally.. depending on the weave of your foundation cloth it'll be pretty warm, and heavy by the time you're finished.
for a 9 1/2 window, you would start with a 16 1/2 inch square, I would think....