simmer up

simmer up (third-person singular simple present simmers up, present participle simmering up, simple past and past participle simmered up)

1. (informal) To cook a food through simmering.

   First, simmer up a portion of peas.

2. (figuratively, by extension) To arise, usually of an emotion, as if from a steamy, simmering action.

   Emotions simmered up when he saw his wife again.