What is adverb for the word spicy?

There isn't a single perfect adverb for "spicy." However, depending on the context, you could use:

* Spicily: This is the most direct adverb form of "spicy," but it's not very commonly used.

* Sizzlingly: This emphasizes the hotness and intensity of the spice.

* Fiercely: This emphasizes the strong, aggressive flavor.

* Warmly: This suggests a pleasant and comforting spiciness.

* Hotly: This emphasizes the heat of the spice.

The best choice will depend on the specific situation and the kind of spiciness you want to describe.