Bring a large pot of salted water to boil and cook linguine per package directions until al dente. Drain, reserving 1/4 cup pasta water, and set aside.,While the pasta cooks, season sliced chicken with salt, pepper, and paprika.,In a large skillet over medium‑high heat, heat olive oil and sauté chicken until golden and cooked through, about 5–7 minutes. Remove and set aside.,In the same skillet, melt butter. Add garlic, red pepper flakes, thyme, and lemon zest; cook ~1 minute until fragrant.,Stir in Dijon mustard, lemon juice, and roasted red peppers. Cook 2 minutes.,Optional: Add heavy cream and simmer 2–3 minutes until sauce thickens slightly.,Return chicken to skillet and toss in cooked linguine. Add reserved pasta water a few tablespoons at a time if needed to loosen the sauce.,Stir in chopped parsley and season to taste with salt and pepper.,Serve topped with grated Parmesan and extra parsley.