Some people don't like okra, but they're crazy. Many people who claim not to like okra will like it this way, cooked with Indian spices. The goo that offends some people becomes an integral part of the curry gravy. This is similar to a Nepali preparation of the dish, but I don't remember exactly what went into that (it had tomatoes, turmeric and fenugreek), so I won't claim that this is Nepali.
Start with washed and chopped okra.
Heat some oil in a pan and add cumin seeds, mustard seeds, and fenugreek seeds. The mustard and fenugreek seeds can be pungent, so don't use too many. Cumin seeds are much milder and can be used in greater quantites. Once the mustard seeds start popping, add onions and let them soften.
With okra, I tend to use fewer spices in the masala. Add tumeric, ground fenugreek, ground cumin, salt, and chili powder (you could add chilis to the onions instead of chili powder). Mix the ground spices in the oil and let them fry up a little before adding the okra.
Let the okra cook until its soft. Don't rush it, as you want to cook out all the slime, which will end up mixing with the spices. Add diced tomatoes and cook until they soften up as well. You don't want the tomatoes to liquify, just cook a little.
Serve with rice or another grain, or simply as a side dish, especially slow cooked or BBQ meat.