Bring a large pot of salted water to a boil and add the pasta to the water. Cook the pasta until al dente (5-7 minutes).
Before straining the pasta, remove 1 cup of the pasta water from the pot and set it aside.
Strain the pasta, rinse with warm water and set aside.
Next, heat a large skillet over medium/high heat. Add olive oil.
When the olive oil is fragrant add the onion to the skillet and sprinkle with ⅛ teaspoon salt. Cook the onion for 2-3 minutes.
Add the garlic to the skillet and toss with the onion. Sauté the garlic for 1-2 minutes or until fragrant.
Deglaze the pan with the white wine. Toss the onion and garlic with the white wine.
Add the starchy water to the skillet and bring to a gentle boil.
Turn the heat to low and let the sauce reduce and thicken for 4-5 minutes.
Add the lemon juice to the skillet and simmer for 1-2 more minutes.
Lastly, Add the butter and remaining salt to the sauce and stir until the butter melts.
Add half of the pasta to the skillet and toss it with the sauce. Add the rest of the pasta to the skillet and toss until all the pasta is covered in sauce.
Top with grated parmesan cheese, cracked pepper, parsley, and fresh lemon.