helping one who has potential to rise to power, seeking for future returns (slang)
Definitions (粵典–words.hk)
動詞
關心或者奉承一啲未得勢或者冷門黑馬，為將來鋪路 to support someone who has fallen from power, to work on behalf of someone who has lost power or status in the hope that they will regain their former position; literally: to warm a cold stove
動詞
押注落啲大冷盤度 to bet on a black horse
如果呢轉冷灶燒得起，佢一定賺到喊。
如果呢转冷灶烧得起，佢一定赚到喊。
If his bet on his black horse pays off, he will turn a big profit.