This pattern, and YouTube video is a demonstration of how to make a “Bavarian Stitch Square”. The designer rates this as an INTERMEDIATE level.
In the video, she states that she is using a DK (#3) weight yarn, but she does not specify WHICH yarn, only that she is using DK weight with a 4.5mm hook.
From the designer’s website: .
“Learn how to crochet this absolute classic technique - the Bavarian Stitch. Definitely one to wow people with! It is easy once you get the hang of it so if you have always been tempted, why not give it a go? A stunning textured square - perfect for blankets or cushion / pillow covers.”
Written pattern is here: https://www.hookedbyrobin.com/blog/crochet-bavarian-stitc...
YouTube video is here: https://www.youtube.com/watch?v=4I1KbQWtdBU