Start by heating the oil in a large skillet over medium-high heat until shimmering and fragrant. Add the finely chopped onions and sauté, stirring often, for about 5 minutes until they turn golden and smell sweet.
Add the minced garlic along with the ground cumin and turmeric. Cook for about 30 seconds, stirring gently, until the spices release their aroma and become fragrant.
Next, toss in the sliced mushrooms, stirring well to coat them evenly with the spice mixture. Continue cooking over high heat for about 10 minutes, stirring occasionally, until the mushrooms shrink, darken, and release a smoky aroma.
Stir in the chopped tomatoes and cook for another 5 minutes until the tomatoes soften and release their juices, creating a rich, slightly saucy texture.
Season with salt to taste and cook for an additional 2 minutes, allowing flavors to meld and the mushrooms to become tender and slightly crispy around the edges.
Finish by stirring in chopped cilantro or parsley, then squeeze a little lemon juice over the top. Give everything a final stir, then remove from heat and serve warm, garnished with extra herbs if desired.