The commercial letters of the Cairo Geniza are an underutilized documentary source base for Muslim Sicily. The letters of the Geniza merchants reveal a dense network of economic and social ties that stretched across the length and breadth of the Islamicate Mediterranean. However, working with the documentary Geniza presents paleographical, linguistic, and methodological challenges. The aims of this paper are twofold. The first is to argue for a different methodological approach towards using the documentary Geniza to shed light on Muslim Sicily, one that prioritizes working directly with original documents and placing them in the greater context of Mediterranean trade. This approach is necessary because relying on existing English-language publications of Geniza documents severely limits the existing source base. English publications on Sicily in the Geniza also take the sources out of their greater Mediterranean context, restricting researchers’ ability to go beyond illustrative examples and discuss broader social and economic trends. The second aim of this paper is to apply the proposed methodology to enhance our understanding of the flow of resources (such as taxation, agricultural products and other trade goods) with and within Muslim Sicily, illuminating its role in the triangular trade with its two major trading partners, Egypt and Ifrīqiya. Focusing primarily on the grain trade, this paper will demonstrate Sicily’s enduring role as a Mediterranean grain basket as well as the social and political implications of Sicily’s grain exports both for its trading partners, and for everyone (peasants, merchants, administrators) who facilitated the flow of grain within the island itself.