Oatmeal stitch
Oatmeal stitch is made up diagonal rows of two different sizes of square stitches which are worked in the opposite direction from each other.
The smaller squares are like elements of reversed cushion stitch.
Method
Begin by working a diagonal row of interlocking square stitches. Make a tent stitch across one intersection of the canvas.
and then below it make stitches across two, three, four, three, two then one intersection again to form a square.
Repeat step two across the diagonal of the area being worked (note that the stitch ‘encroaches’ which means there is only one of the shortest stitches where the squares meet).
Once this row is complete make the smaller square stitches in the spaces. These begin with a reversed tent stitch, then a stitch across two,
three, two then one intersection of the canvas.
Repeat these along the row. The longest of the stitches should touch at the corners.
The next row is a repeat of the first. The longest stitches of these squares should touch the longest stitches of the previous row of large diagonal squares.

Common uses
The two different directions of the stitches in this pattern give it an interesting texture. Oatmeal stitch has a fairly large pattern repeat, but it is good for back grounds.
Embroidery Techniques
Related Stitches
Identifying Oatmeal stitch
This stitch combines two different sizes of diagonal square stitches, which are worked in the opposite direction from each other.
References
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Rachel Doyle, RSN Essential Stitch Guides: Canvaswork (2013) , p.73
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Various Authors, The Royal School of Needlework Book of Embroidery (2018) , p.117