沸かす
わかす · wakasu · JLPT N4 · verb-godan
to boil
🫖🔥 waka-su: walk a soup to the stove and boil it
沸かす is the transitive partner of 沸く (waku, to come to a boil): you boil something, as in お湯を沸かす, to boil water. The -asu ending marks making it happen. 沸 = water radical 氵 + 弗, so the character itself carries the liquid.