In a large mixing bowl, combine fresh lemon juice, corn starch, ground cumin, ground turmeric, garam masala, and salt. Whisk until smooth and well-combined. Add cauliflower florets, tossing to coat evenly.

Heat olive oil in a skillet over medium-high heat. Add coated cauliflower in a single layer and sauté for 7-8 minutes until golden brown and tender, stirring occasionally.

Lower the heat and return remaining cauliflower and corn starch mixture to the skillet. Cook for another 7-8 minutes, stirring frequently, until charred and crisp-tender.

In the same skillet, add more olive oil and unsalted butter. Once melted, add chopped yellow onion and sauté for about 8 minutes until translucent.

Stir in minced garlic and grated fresh ginger. Cook for 2 minutes until fragrant.

Sprinkle in additional ground turmeric, garam masala, salt, paprika, and ground cinnamon. Mix well and let simmer for 1 minute.

Pour in tomato sauce and vegetable broth, stirring to combine. Bring to a gentle boil, then reduce to a simmer and cook for 5 minutes.

Return sautéed cauliflower to the skillet, gently stirring to coat in the sauce. Simmer for 15 minutes uncovered, stirring occasionally.

Remove from heat and garnish with freshly chopped cilantro. Serve over basmati rice with a dollop of Greek yogurt on top.