Preheat the oven to 400°. Melt 1 teaspoon of the butter in a small saucepan. Add the shallots and cook over moderate heat until softened, about 2 minutes. Add the wine and boil over high heat until reduced to a thick, syrupy glaze, 5 to 7 minutes. Transfer to a small bowl and let cool. Stir in the remaining 2 tablespoons of butter until thoroughly blended, then add the chopped parsley and season with salt and pepper.
Lay the salmon on a work surface and press the whole parsley leaves and thyme leaves on the fillets. Season with salt and pepper and wrap 2 slices of pancetta around each piece of salmon.
In a pie plate, toss the pearl onions with 1 teaspoon of the olive oil. Cover with foil and bake for about 20 minutes, or until softened and slightly caramelized. Let cool slightly, then trim the root ends and peel the onions.
In a large skillet, heat 1 tablespoon of the oil until shimmering. Add the escarole, season with salt and pepper and cook over moderately high heat, tossing, until tender, about 5 minutes. Add the pearl onions, chicken stock and lemon juice. Cover and keep warm.
Heat the remaining 2 teaspoons of olive oil in a large nonstick skillet. Add the salmon fillets and cook over high heat, turning, until the pancetta is browned all over and the fish is medium rare, about 7 minutes. Carefully transfer the salmon to paper towels to drain.
Transfer the escarole and pearl onion mixture to 4 warmed plates and set the salmon on the greens. Top each fillet with a little of the red wine butter and serve at once.
The recipe can be prepared through Step 3 and refrigerated for up to 1 day.
A rich, deep, oak-aged California Chardonnay would balance the strong flavors of the salty pancetta and the sharp escarole. If you'd prefer a red, consider a flavorful light Pinot Noir from California or Oregon.