Season chicken breasts with Cajun seasoning, salt, and pepper.
Heat olive oil in a skillet and sear chicken 5-7 minutes per side. Remove and set aside.
Cook pasta in salted boiling water until al dente, about 8-10 minutes. Drain and set aside.
In the same skillet, melt butter and sauté garlic until fragrant. Add heavy cream, chicken broth, and smoked paprika; simmer.
Stir in Parmesan cheese until sauce is creamy. Slice chicken and add to the sauce with cooked pasta. Finish with lemon juice, parsley, and red pepper flakes.
Notes
For extra flavor, add sautéed vegetables or shrimp.