Jean Baptiste Labat, Nouveau Voyage aux Iles d'Amerique. Paris: Guillaume Cavelier, 1772, vol. 2, p. 39,
Cassava flour recipe from The Jamaica Cookery Book
Sullivan, Caroline. "Baked Cassava and Bammy Cakes."The Jamaica Cookery Book: Three Hundred and Sixty Four Simple Cookery Receipts and Household Hints. Aston W. Gardner & Co, 1897. Kingston, Jamaica.
This is how cassava flour was made by slaves and indigenous people. In the video, it mentions that cassava flour could be dried using the sun instead of an oven; this is most likely how slaves and indigenous people would dry the flour. They would also use tools made from natural substances such as rock to grind the flour
Source: Pink Angels Kitchen. HOMEMADE CASSAVA FLOUR | How to Make Cassava Flour. YouTube, 15 Mar. 2018.