Subject + 的 + 最爱 / 最爱 + 是 + Noun
爱 (ài) can function as a noun meaning "love" or "favorite." When used in the pattern 最爱, it means "favorite" or "the thing one loves most." This noun usage is common in casual speech to express strong preference for something.
火锅是我的最爱。
Huǒguō shì wǒ de zuì ài.
Hot pot is my favorite.
旅行是她一生的爱。
Lǚxíng shì tā yìshēng de ài.
Traveling is the love of her life.
这首歌是很多人的最爱。
Zhè shǒu gē shì hěn duō rén de zuì ài.
This song is a favorite of many people.