正合猴意 Just to the Monkey's Liking
行者聞言，暗喜道：「正可老孫之意，這一向不曾洗澡，有些兒皮膚燥癢，好歹燙燙，足感盛情。」頃刻間，那油鍋將滾。行者闻言，暗喜道：「正可老孙之意，这一向不曾洗澡，有些儿皮肤燥痒，好歹烫烫，足感盛情。」顷刻间，那油锅将滚。
逐句解 Line by line
The Pilgrim, hearing this, said to himself in secret delight: "This is just to old Sun's liking. I haven't had a bath this long while, and my skin is a bit dry and itchy; a good scalding, whatever comes of it, would be a real kindness."
The bravado reaches its high-water mark here. 正可老孫之意, "just to old Sun's liking"; he has not had a bath in a while, his skin itches, and a good scalding would be a kindness. 燥癢, zào yǎng, dry and itchy. 好歹燙燙, "a scalding, whatever comes of it," with the verb doubled to make it casual. 足感盛情, zú gǎn shèng qíng, "deeply obliged for your kindness," is a set formula of thanks — the polite phrase you would write on a card, dropped into a sentence about being boiled alive. The suffix 兒 is ér. Note 暗喜: he is not putting on a brave face, he is genuinely pleased, which tells the reader he already has a plan.
In an instant, that oil-cauldron was about to boil.
頃刻間, in a moment. 將滾 takes 將 as jiāng, "about to" — the same word that opened the chapter with rice nearly ready. The oil is nearly ready now.
A death sentence answered as an offer of a hot bath. He has not washed in a while, his skin is dry, and a good scalding would be 足感盛情 — a kindness he is deeply obliged for, which is the phrase you use to thank someone for a favour. It is the boldest thing he says in the chapter.
But the giveaway is 暗喜, "secretly delighted." He is not being brave; he is pleased, and the reader is meant to notice. Somewhere in the last few sentences Wukong has worked out how to get out of this, and the next passage will show us what he saw when he looked around.