Arrange the sweet potato slices, overlapping, in a medium baking dish.
In a small bowl or jar, mix together the sesame oil, stock, coconut milk, lemongrass, ginger, garlic, chilli and lime juice. Pour 3/4 of the mixture over the potatoes (leaving a small amount for later). Roast sweet potatoes for 20-30 minutes, or until potatoes are cooked. About 8-10 minutes before the cooking time is up, remove tray from oven and place the salmon on the potatoes, add asparagus spears and tomatoes and top with the rest of the coconut mixture.
Serve fish with sweet potato, asparagus and tomatoes and pour juices over the top. Top with fresh coriander and serve with lime wedges. Option to add a drizzle of soy sauce.
