For the Shrimp

1. Add the shrimp to a small bowl or large measuring cup, along with the kosher salt, sugar, and zest. Add just enough cold water to cover it, and stir to dissolve the salt and sugar. Let sit for 20 minutes.
2. After 20 minutes, rinse and drain the shrimp on paper towels.
3. When ready to cook, heat about 2 tablespoons of olive oil and 1 tablespoon of butter over medium-high heat. Add crushed red pepper if using, and saute shrimp for 1-2 minutes per side. If using smaller shrimp, adjust the cooking time as needed. You don’t want rubbery overcooked shrimp. When shrimp is opaque and pink, turn off the heat, toss the shrimp in the oil and butter mixture, and add a splash of lemon juice. Add the shrimp to the pasta dish and enjoy.

For the Aglio Cacio e Pepe

1. Bring a quart of water to a boil in a pot, adding a very large pinch of sea salt once it starts boiling. Add the spaghetti, gently folding it in so it fits under the water. We are using far less water here on purpose — we want extra starchy pasta water. Do NOT break the spaghetti, just be patient and gently swirl it in until its submerged. Cook according to package directions, minus 2 minutes.
2. Meanwhile in a large skillet over medium-low to medium heat, bring the olive oil, butter, black pepper, and garlic to a gentle simmer. Stir the garlic around frequently so it doesn’t burn. Also, because we’re using butter, the milk solids will brown over time. Keep this mixture moving so nothing burns. You want the garlic to be toasty and straw colored at the most. This will cook for about 5-7 minutes.
3. Once the garlic is toasty and lightly golden brown around the edges, reduce the heat to low. Add a ladle of the hot starchy pasta water to slow down the cooking process. Stir around to scrape up any browned bits (if you have any). Add another ladle of the pasta water, then add the pasta. Keep the pasta water nearby because this is what the base of our sauce will be comprised of. As soon as you add the pasta, stir vigorously to coat each strand in the oil/butter and water mixture. It should begin to emulsify. Immediately add the pecorino romano while stirring and mixing until it’s creamy and fully emulsified. Continue to add starchy pasta water until it’s the consistency you prefer. Taste and adjust with salt and pepper as needed. Cover and keep warm. Keep the pasta water to later adjust the consistency while you prepare the shrimp.
4. Top the pasta with shrimp, fresh parsley, more pecorino, and toasted breadcrumbs (if using).
5. Enjoy immediately.