Drizzle oil over medium-high heat on a griddle. Add the sausage, bell peppers, and onion. Season with fajita seasoning and toss to coat. Cook until the vegetables are tender and the sausage is heated through, adding 1 tbsp of garlic paste for extra seasoning.
Add the cooked pasta to the griddle. Season again with fajita seasoning and 1 tbsp of garlic paste. Stir in the butter, allowing it to melt and coat the pasta.
Add the whipped cream cheese and heavy whipping cream, tossing to melt and combine evenly with the pasta. Stir in the Parmesan cheese, mixing well. Add more Parmesan if desired, along with some chopped parsley or cilantro.
Plate the dish and garnish with extra Parmesan cheese and parsley. Serve immediately.
