It literally tastes like it has been slow simmering for hours. (howtofeedaloon.com)
A long, slow simmer of mushrooms and vegetables, with select herbs and spices, creates a deeply flavorful soup base while you're off doing other things. (soupaddict.com)
Bring to the boil and lower the heat so the liquid is at a very slow simmer. (thelowfodmapgourmet.com)