Bring a large pot of salted water to a boil. Add fettuccine or linguine and cook according to package instructions until al dente, about 8-10 minutes. Reserve ½ cup of pasta water, then drain the pasta.

In a large skillet, melt unsalted butter with olive oil over medium heat. Add onion and red bell pepper and sauté for 3-4 minutes until soft. Add minced garlic and cook for an additional 1-2 minutes.

Pour in heavy cream and chicken broth into the skillet, stirring well. Bring to a gentle simmer over medium-low heat. Allow the sauce to thicken for about 5-7 minutes. Stir in Parmesan cheese and lemon juice, seasoning with salt and pepper.

Fold in lump crab meat carefully, cooking over low heat for 2-3 minutes until warmed through.

Add drained pasta to the skillet with the sauce. Toss gently, adding reserved pasta water to adjust sauce consistency.

Plate generously, garnishing with freshly chopped parsley and additional grated Parmesan. Serve with garlic bread and salad.