In a medium saucepan, heat 1 tablespoon of the olive oil. Add the shallot and cook over moderate heat until softened, about 4 minutes. Add the thyme sprig, black pepper, red wine and balsamic vinegar and boil over high heat until reduced to 2 tablespoons, about 12 minutes. Remove the pan from the heat and whisk in the cream, then whisk in the butter, 1 tablespoon at a time. Season the sauce with salt and pepper. Strain into a bowl and keep warm.
In a large nonstick skillet, heat the remaining 1 tablespoon of olive oil until shimmering. Season the salmon fillets with salt and pepper and add them to the skillet, skinned side up. Cook over moderately high heat until the fillets are browned, about 4 minutes. Turn the salmon and cook over moderate heat until the fish is just opaque throughout, about 3 minutes longer. Transfer the salmon to plates, spoon the sauce over the fish and garnish with ground black pepper. Serve immediately.