Heat the large skillet over medium and add the oil, shimmering gently. Toss in the diced onion and sauté for 3-4 minutes until it turns translucent and begins to smell sweet and fragrant.
Add the minced garlic and cumin seeds to the skillet. Cook for about 30 seconds until the garlic releases a warm, toasted aroma and the seeds start to crackle slightly.
Stir in the turmeric and ground coriander, cooking for another minute until the spices shimmer and become fragrant, filling the kitchen with a warm aroma.
Pour in the crushed tomatoes and cook for 5 minutes, stirring occasionally, until the sauce darkens slightly and thickens, releasing a tangy, sweet aroma.
Add the drained chickpeas to the skillet, stirring to coat them with the sauce. Let simmer for about 10 minutes, allowing the flavors to meld and the sauce to gently thicken.
Stir in the fresh spinach, handful by handful, until it wilts and turns a vibrant green, which takes about 2 minutes. The spinach should be tender but still bright.
Taste the curry and add salt as needed. Squeeze in the fresh lemon juice to brighten the flavors. Stir well to combine.
Remove the skillet from heat and let the curry rest for a couple of minutes, allowing the flavors to settle. Serve hot with rice or flatbread, garnished with herbs if desired.
