Butter or cooking oil spray
1 onion, thinly sliced
1 1/2 pounds skin-on salmon fillet
1 cup white wine, vegetable broth or water
2 tablespoons freshly squeezed lemon juice
2 tablespoons melted butter
1 teaspoon kosher salt
1/4 teaspoon freshly ground black pepper
4 garlic cloves, minced
Sauce
2/3 cup heavy cream
1/4 cup chicken broth, water or white wine
1/8 teaspoon lemon zest
Chopped fresh parsley
Lemon wedges
Grease the slow cooker with butter or cooking spray. Arrange the onion slices in a layer covering the bottom of the pot.
Arrange the salmon in a single layer on top of the onions.
In a small bowl, stir together the wine, lemon juice, melted butter, salt, pepper and garlic. Pour the mixture over the fish.
Cover the slow cooker and cook on low for two hours. The salmon should be cooked through and flake easily with a fork.
In a small saucepan, combine the lemon juice, broth and cream, and bring it to a simmer over medium heat.
Reduce the heat to low, cover the pot, and simmer for eight minutes. Remove the lid and raise the heat to medium-high.
Stir in the zest and cook, stirring occasionally, until the sauce is slightly reduced and thickened, about two minutes. Taste and add salt as needed.
Spoon the sauce over the salmon and garnish with parsley and lemon wedges.