Content refers to components of the menu beyond pricing & availability: Images, description, translations, nutrition & allergens, and so on.
For menu content, Sanity is always the source of truth. The majority of the menu information is captured in Sanity as user input, however, some of the information is retrieved from MDM. For more context about Sanity & MDM:
[MDM Page]
While configuring the content in Sanity, starting from bottom to top in the menu structure hierarchy would make your menu creation composition a lot easier:
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