First, bring a large pot of water to a boil then generously salt the water. It should be as salty as seawater.

Meanwhile, prepare all of the ingredients. Finely dice the shallots, mince the garlic cloves, and optionally split the fresh snap peas open into two halves. Pick the thyme leaves off of the stems and gather the rest of the ingredients.

Heat up large skillet over medium heat on the stove. Once the pan is hot add the olive oil followed by the shallots and garlic and sauté them stirring occasionally until they start to brown, about 3 minutes.

Add the pasta to the large pot of salted water, give it a good stir so it doesn't stick, and cook it until about 1 minute under al dente following the cooking time on the package.

Add the fresh snap peas fresh peas (if using) to the skillet, season everything with salt and pepper, and let them cook for 1-2 minutes. If using frozen peas wait to add them.

Drain the pasta and reserve some of the pasta cooking water then add the pasta to the skillet and lower the heat. Add about 1/2 cup of pasta cooking water to the pan to help create a sauce. Add the frozen peas now if using them.

Stir in the butter, lemon zest, lemon juice, and grated parmesan cheese, and add more pasta water as needed to keep the sauce loose.

Remove the pan from the heat. Serve immediately with more grated parmesan cheese and lemon zest.