Preheat oven to 400 degrees. Line baking sheet with foil, grease lightly, and lay salmon on top with prawns. Season with salt and pepper to your taste. Add thin slices of lime around the baking sheet and top with cilantro.
Melt butter in a medium saucepan, over medium -high heat. Stir in honey, siracha sauce, juice of one lime, soy sauce and garlic. Bring to a boil, then reduce to medium heat and cook for 3-4 minutes more for sauce to thicken.
Pour sauce over salmon and prawns by making sure all the seafood is covered completely. Fold the edges of the foil up around the salmon and prawns so the sauce does not spill out.
Bake for 15 minutes, then switch to broil and cook for another 4-5 minutes.
Top salmon with hot honey, chopped cilantro and serve.