1901.90.66.00 - Described in general note 15 of the tariff schedule and entered pursuant to its provisions

This HTS subheading encompasses a specific category of food preparations that are not elsewhere specified or included within Chapter 19. It primarily covers malt extract and a broad range of other food preparations derived from cereals, flour, groats, meal, starch, or malt extract. Crucially, these preparations must not contain cocoa, or if they do, it must be less than 40 percent by weight on a totally defatted basis. Additionally, this classification extends to food preparations of goods from headings 0401 to 0404 (dairy products), provided they contain less than 5 percent by weight of cocoa calculated on a totally defatted basis.

The "Other" designations at this level indicate that this category is a residual grouping for items that do not fit into more specific subheadings within Heading 1901. It's important to differentiate these preparations from those that might contain higher percentages of cocoa, which would be classified under different subheadings within 1901, or from finished baked goods that fall under other chapters. The key classification criteria are the origin of the ingredients (cereals, dairy, etc.), the absence or limited presence of cocoa, and the fact that they are prepared foodstuffs not specifically detailed elsewhere.

As this subheading is a leaf node, there are no further subdivisions. Classification into 1901.90.66.00 signifies that the product has met all the preceding criteria within Heading 1901 and is considered an "other" preparation of the types described. Examples might include certain types of fortified flours, soluble coffee preparations (if meeting the cocoa criteria), or specialized infant cereals that do not contain cocoa. The governing principle for classification here is the "not elsewhere specified or included" clause, making this a catch-all for qualifying prepared foodstuffs within the scope of Heading 1901.