Heat oil in a large flat-sided skillet over medium heat. Add onion; cook and stir until translucent, about 5 minutes. Add mushrooms and garlic; cook and stir until softened, about 2 minutes. Add yam and cook for 2 minutes.
Stir cumin, coriander, onion seeds, black mustard seeds, chile powder, paprika, and turmeric into the skillet; cook and stir until evenly distributed, about 2 minutes. Add cauliflower, chickpeas, salt, and black pepper; stir until combined.
Mix vegetable stock and tomato paste together in a small bowl; pour into the skillet. Cover and cook until yam is tender, about 15 minutes. Stir in spinach, parsley, lemon juice, and lime juice and cook until flavors combine, about 1 minute.