Heat a wok or large skillet over medium-high heat and add the vegetable oil. When shimmering, toss in the cumin seeds and let them crackle for about 30 seconds, releasing a fragrant aroma.
Add the diced onion and cook, stirring frequently, until translucent and just starting to turn golden, about 3-4 minutes. The smell should turn sweet and savory as the onions soften.
Stir in the grated ginger and minced garlic, cooking for about 30 seconds until fragrant. You’ll notice a warm aroma filling the air, signaling the spices are blooming.
Add the chopped bell pepper and diced tomato to the pan. Cook for 5-6 minutes, stirring occasionally, until the vegetables are tender-crisp and the tomato has released its juices, bubbling gently.
Stir in the ground coriander, cumin powder, and garam masala. Toast the spices for about 1 minute, allowing their aroma to intensify and the spices to bloom, coating the vegetables evenly.
Pour in water or vegetable stock, stirring to loosen the mixture and create a sauce. Reduce the heat to medium and let it simmer for 2-3 minutes, allowing the flavors to meld and the sauce to thicken slightly.
Season with salt and pepper to taste. For brightness, add a squeeze of lemon juice if desired. Give everything a gentle stir to combine.
Turn off the heat and sprinkle the chopped fresh coriander over the top. Let the dish rest uncovered for 2 minutes to allow the flavors to settle and deepen.
Serve your Vegetable Kadai hot with steamed rice or warm naan, enjoying the vibrant colors, fragrant spices, and balanced textures.