In a medium pre-heated skillet, add a little olive oil for searing the fish fillet. Add the fish - skin side up first- and lightly season with salt & pepper. In another skillet while you are searing the fish, heat a little bit of butter, and the shallots and garlic. Lightly brown, and add the grapes and basil. Move around the pan a little being very careful not to burn the shallots or garlic. This will make the sauce taste bad. Add the champagne and allow to reduce for a few minutes. Turn your fish now. Depending on how thick the fillet is, you will probably need to cook the salmon for 4-6 minutes on each side. Be very careful not to overcook the salmon fillet. You can consume underdone salmon as long as you can ensure its freshness. Going back to your other pan, the sauce, lightly season the sauce, and smooth with the remaining butter. You are watching for the bubbles in the sauce to get closer and closer together. Add the juice of half a lemon. Serve the fish with the skin side down on the plate, and gently drizzle the sauce over the fish and serve immediately. Add your favorite side dish and veggies for a complete meal!