This is a super easy embroidery stitch used in Cuibhrichte.
1. Cut approximately 70 cm (28”) of your yarn and fold in half. Thread needle with the doubled yarn.
2. Insert the needle from the inside of the mitt to the outside close to the start of the second braid and pull yarn through, holding the loose end on the inside.
3. Insert the needle behind the first braid (or the last chain stitch worked) and back out on the other side and pull the yarn through.
4. Insert the needle back into the mitt (through the first hole you used) and out again a couple of stitches away. Pull the yarn through. Repeat steps 3 and 4 until you reach the top of the first braid, trying to keep the stitches the same size as the braids.
5. Bring the yarn through the centre of the last braid. Put the needle around the last chain stitch and insert the needle back into the last braid.