Answer:

simmer

Answer	Crossword Clue
SIMMER	Cook without boiling
SIMMER	Not quite boil
SIMMER	Seethe

SIMMER	Almost bubble
SIMMER	Do a slow burn
SIMMER	Soup recipe directive
SIMMER	Experience inner turmoil
SIMMER	Keep just below a boil
SIMMER	"... down!": cool it!
SIMMER	Ferment
SIMMER	Cook slowly

SIMMER	Slow boil
SIMMER	Make a reduction
SIMMER	Cooking direction.
SIMMER	Ferment or poach
SIMMER	Come to a boil
SIMMER	Stew
SIMMER	Make minestrone
SIMMER	Recipe direction

SIMMER	Cook just below the boiling point
SIMMER	Braise