Line a large heavy baking sheet or baking dish with aluminum foil.
Place baking sheet in oven and preheat to 425 degrees F.
Add cubed potatoes to a saucepan with enough water to cover the potaotes. Stir in 1/4 tsp turmeric and bring to a boil.
Simmer for 7 minutes or until partially cooked (potatoes should be parboiled: barely tender when pierced with a skewer).
Drain potatoes and set aside.
In a small bowl, mix brown sugar, 1/4 tsp turmeric, cayenne, garam masala, salt with lemon juice and oil.
Place potatoes, onions, cauliflower and garlic into a large bowl, and pour oil mixture over the top and stir to coat.
Once the oven has reached the desired temperature, remove the baking sheet and drizzle with vegetable oil.
Transfer contents of bowl to the baking pan.
Place baking pan on the center rack of the oven.
Bake for 30 to 40 minutes or until vegetables are cooked through and lightly charred, stirring the cauliflower mixture halfway through.
Garnish with cilantro.
I use a stoneware baking sheet to roast the cauliflower. When you transfer the contents of the bowl to the baking sheet, watch out for splatters because the vegetables are wet and the baking sheet is hot, hot, hot.
Recipe by Paint the Kitchen Red at https://www.paintthekitchenred.com