One pot, thirty minutes, 45g of protein, and it is better reheated. Use thighs, not breast — this is the dish where that choice is not a compromise.

The combination here is not an accident: this is one pot that puts calcium, iron and protein on the plate at the same time, which is the practical problem for a lot of women after forty.
Kale is one of the few green vegetables whose calcium is well absorbed — spinach contains more calcium on paper, but binds most of it up as oxalate. Kale is low in oxalate, and absorption from it compares well with dairy. After menopause, falling oestrogen speeds bone loss, and calcium intake is the part of that within reach.
Kale and butter beans both carry non-haem iron, the plant form, which is absorbed poorly on its own. That is what the lemon at the end is for — vitamin C markedly increases non-haem iron absorption, and adding it after the heat keeps it intact. The chicken helps too: haem iron from meat improves absorption of the non-haem iron eaten alongside it. If periods are heavy, this matters more than most supplements do: iron deficiency and fatigue.
Thighs rather than breast is a real recommendation, not a shortcut. Thigh meat carries more zinc and iron than breast, it holds moisture through reheating, and it costs less.
It keeps four days and freezes. The beans thicken the broth by the next day.