Heat oil in a large saucepan over medium heat and add cumin seeds and dried red chilies, cooking until fragrant and the cumin seeds start to crackle, about 30 seconds.
Add the finely chopped onion to the pan and sauté until it turns translucent and begins to brown slightly, about 5-7 minutes. The kitchen will fill with a warm, caramelized aroma.
Stir in the minced garlic and grated ginger, cooking for another minute until aromatic and slightly golden, releasing a burst of fragrant fumes.
Add the blended tomatoes along with turmeric powder and coriander powder. Cook this mixture on medium heat, stirring occasionally, until the oil separates and the sauce darkens slightly, about 10 minutes. It will smell sweet and spicy as it thickens.
Pour in the chopped vegetables and stir well, coating them with the spicy tomato sauce. Cook for 5-7 minutes until the vegetables begin to soften but still retain some crunch.
Pour in about a cup of water or as needed to cover the vegetables slightly. Stir in salt to taste and bring everything to a gentle simmer. Cover the pan with a lid and cook for 15 minutes, allowing the flavors to meld and the vegetables to become tender.
Remove the lid and stir in garam masala. Increase the heat slightly to let the curry thicken uncovered for another 3-5 minutes, stirring occasionally. The curry should be rich and coating the vegetables evenly.
Garnish with chopped cilantro for a fresh, herbaceous finish and an inviting pop of green color.
Serve hot with steamed rice or Indian bread, enjoying the vibrant, spicy flavors and tender vegetables coated in the thick tomato gravy.