When my children were young this was one of their very favourite meals.
There were always plenty of vegetables in the garden or the freezer, and we used whatever was available. The recipe was never the same twice. This (above) was what I used yesterday.
I lightly boil the Potatoes and Beans in advance, then fry all the others together until nearly cooked; only then do I add the Potatoes and Beans to the rest. I season, add garlic butter, and finish off with a light sprinkling of ground Cumin powder. Everything should be slightly browned.
Often veggie meals leave me wanting some 'meat', but this one never does.