I appreciate your perspective, and you have both made valid points about the precision implied by the word "requires." In this context, using "plenty of" aligns with the idea of specifying a sufficient and satisfying amount of sugar for the recipe. Language is flexible and can be interpreted differently. Both interpretations are valid, grammaticaly correct and it's interesting to consider different approaches to convey the intended sweetness level.

Requires is specific to an amount. When I hear "requires" I think of an exact amount: 50g or 2 cups of sugar. You could say "The recipe has enough sugar for it to be sweet" or "That's plenty of sugar to make it sweet..."

Just my humble opinion, but I think enough is acceptable in the sentence

Anyone who can help with Mongolian language, I will be glad to offer English language. Thanks