I just had to see if I could do it

I was stacking pieces laying on my cutting table and when these 2 ended up together, I thought that is kind of interesting, I wonder if I can remember how to "set in" one piece into another.

I started by marking the size "hole" I would need and sewing around it with a straight stitch.
Then I cut the "hole" 1/4" in from the stitching line.
I clipped into the corners.
Then I started sewing the patch into place with 1/4" seam.
Sewing in the last side.

The finished piece. Now I just have to decide what to make it into.