Trim tips and stems off okra, and cut pieces along a diagonal bias. (Try to use pieces no larger than 2 inches. This recipe works best with young okra, as it is most tender.)
In a sauté pan, heat oil over medium-high heat until shimmering. Add mustard seeds; cook, stirring constantly, until bubbles appear around seeds and they begin to pop. Add onion and curry leaves; cook for 2 minutes, stirring constantly. Add garlic; cook, stirring constantly, until onion is just translucent, about 2 minutes. Add salt, cumin, coriander, pepper, and turmeric; stir to combine. Add tomatoes, and toss to coat. Reduce heat to medium.
Add okra, and toss to combine. Cook, uncovered, for 3 minutes. Cover, reduce heat to medium-low, and cook 3 to 5 minutes more. Uncover and check for tenderness. Cook, uncovered, until desired tenderness is achieved. (Once okra is fork-tender it is done.) Add additional salt to taste, if needed.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/samanthas-southern-okra/