For the sweet potato hash: Bring a large pot of water to a boil. Blanch the sweet potatoes until fork-tender.
Drain and set aside.
Heat a saute pan over medium-low heat.
Add the bacon and cook until soft and lightly crisp.
Add the sweet potatoes and pan-fry until the potatoes are lightly browned and crispy, 3 to 4 minutes.
Add the garlic and onions, stirring to incorporate into the hash, and cook until transparent, another 4 minutes. Season with salt and pepper. Keep warm and reserve.
Mix together the mangoes and jalapenos in a bowl. Fold in the jerk sauce and reserve.
Whisk together the Dijon mustard and lemon juice in a bowl. Stream in the oil, whisking until the dressing is emulsified. Season lightly with salt and pepper. Stir in the chives.
Sprinkle the salmon with salt and pepper.
Heat a 12-inch saute pan with the grapeseed oil until hot.
Add the salmon and cook about 4 minutes on each side (or until the desired internal temperature).
Add the butter to the pan and when melted, spoon over the fish.
Transfer the fish to a paper-towel-lined plate to drain slightly.
To plate: Spoon some hash in the center of each plate and top with a piece of salmon. Spoon some jerk mango salsa on top of the salmon, followed by some lemon vinaigrette.