Bring a large pot of salted water to a boil. Cook the linguine according to package directions until al dente. Reserve ½ cup of pasta water before draining, then set the pasta aside.

Heat olive oil in a large skillet over medium-high heat. Season chicken pieces with salt and pepper, then cook for 5-7 minutes, turning occasionally, until golden brown and cooked through. Remove chicken from skillet and set aside.

In the same skillet, melt the butter over medium heat. Add minced garlic, paprika, and red pepper flakes (if using). Sauté for about 1 minute until fragrant, being careful not to let the garlic brown.

Stir in the Dijon mustard, lemon juice, lemon zest, and chicken broth (or reserved pasta water). Gently simmer while scraping any browned bits from the bottom of the pan to incorporate those flavors.

Pour in the heavy cream and add half of the chopped parsley. Stir gently and cook for 2 minutes until the sauce lightly thickens.

Return the cooked chicken to the skillet. Add the cooked linguine and parmesan cheese. Toss everything together to coat evenly, adding reserved pasta water as needed to adjust the sauce consistency.

Taste and adjust salt and pepper as needed. Garnish with the remaining fresh parsley and extra parmesan cheese. Serve immediately while hot.