Heat vegetable oil in a large skillet over medium heat.
Add chopped onion and cook until soft and lightly golden.
Stir in garlic and grated ginger and cook for about 30 seconds.
Add turmeric, cumin, coriander, chili powder, salt, and black pepper.
Stir the spices with the onions for about 30 seconds to release their aroma.
Add cubed potatoes and cook for 5 minutes stirring occasionally.
Add cauliflower florets and mix well with the spices.
Cover the skillet and cook for about 12–15 minutes until vegetables become tender.
Stir occasionally to prevent sticking and ensure even cooking.
Sprinkle garam masala and lemon juice over the dish.
Garnish with fresh cilantro before serving.