The ingredients are up to you. I make my curry sauce by adding my spice mix (cumin, coriander, paprika, tumeric, dry mustard, cayenne, + more) to onions and garlic as they saute. To this I add whatever tomato product I have on hand - fresh diced or canned puree - and a bit of veg stock. For my vegetables, today I added sliced cabbage, spinach, broccoli, and peppers. I let everything simmer for a few minutes and threw in leftover chopped cashews and roasted chickpeas (store-bought) at the end. I served it atop yesterday's rice.
A tip: Because I cook and eat a lot of vegetables, I sometimes do one or two mass cuttings a week. This saves on prep and clean-up time. I can reach in the fridge for a quick snack, too.