I have to admit, it was only a couple of years ago that I came across the term Biscournu. To me it sounds like it should be a biscuity/cake type of thing.
I'm a complete convert now and think these make a lovely present to be gifted to a fellow stitcher.
Start by cross stitching both the part 1 (top) and part 2 (bottom) patterns as you normally would, on separate pieces of Aida.
Then backstitch a border one row away from the edge of the design, going all the way around the outer edge of your finished design using a contrasting colour of thread.
Cut off spare Aida from all four edges, leaving I/2 an inch beyond the backstitch border - keeping the two pieces square.
Fold the edges of spare fabric back with your fingers.
Join a corner of the bottom pattern to the midway point on an edge of the top piece. Using a whip stitch, start sewing the top and bottom of your biscournu together along the backstitched border.
As you pass round a corner section, just keep going the same as on the sides. Although you may want to put extra stitches on the corner sections for strength.
Continue until you have nearly stitched the whole way round the design. Just leave a big enough gap for stuffing. Stuff the biscournu with toy stuffing.
Finish off stitching the sides, securing the thread with a hidden knot.
Sew two buttons - one in the centre of the top, one in the centre of the bottom, passing the thread through the centre of the biscournu to stitch both buttons using the same length of thread.
This is how you get the centre thinner and the corners to point out into the distinct shape of a biscournu.
And there you go, a beautiful pincushion - ready to gift!
If you'd like to stitch the pattern that was used in this tutorial, you can find the pattern pdf here: Spring Biscournu.