In a large pot, bring 4 quarts water and 1 tablespoon salt to boil. Add fettuccine and cook until al dente, about 9 to 11 minutes. Reserve 1 cup of pasta water and then drain well.
Meanwhile, in a large skillet over medium heat, heat butter and oil until melted and combined. Add onion, lemon zest, red pepper flakes, 1 teaspoon salt, and a pinch of black pepper. Cook until softened, about 8 minutes.
Stir in artichokes and sauté until heated through, about 3 minutes. Stir in lemon juice and remove from heat.
To a large serving bowl, add drained pasta, artichoke mixture, ½ cup reserved cooking liquid, and Parmesan cheese. Toss until combined, adding more liquid if needed to bring the sauce together. Season to taste with salt and pepper and garnish with parsley.
