Bring a large pot of salted water to a boil. Add the linguine and cook until al dente according to package instructions. Drain pasta and set aside.
To a large skillet over medium-high heat, add oil. Once hot, add the chicken in a single layer. Season chicken evenly with paprika, garlic salt, salt, and pepper. Cook for 3-4 minutes on one side, or until golden brown.
Nestle 2 tablespoons cowboy butter into the skillet. Flip pieces of chicken and cook until browned and cooked through to an internal temperature of 165°F, another 3-4 minutes.
Remove the chicken from the pan. Place onto a plate and tent to keep warm.
Reduce heat to low. Add the rest of the cowboy butter, heavy cream, garlic salt, and red pepper flakes. Use a spatula to scrape up the brown bits in the pan, and stir until the butter has melted.
Add the cooked linguine and chicken to the skillet, tossing to coat in the sauce.
Add lemon juice. Stir to combine.
Serve the dish garnished with lemon slices.