1. In an extra-large skillet heat 3 Tbsp. olive oil over medium-high. Add the mushrooms and cook, stirring occasionally, 6 to 8 minutes or until brown on the edges and crisp. Add garlic and season with a generous pinch of fine sea salt. Cook and stir 1 minute or until fragrant. Remove from heat. With a slotted spoon, transfer mushrooms to a clean kitchen towel or a couple of paper towels to absorb excess oil. (If you like, set aside a few of the mushrooms to top finished pasta.)

2. Preheat oven to 200°F. Place a very large heat-safe bowl in oven 10 minutes to warm it. (Or fill a very large bowl with hot water; drain water before adding pasta.) In a medium bowl whisk together eggs, Pecorino Romano, Parmesan, and 3/4 tsp. ground black pepper

3. In a large pot or Dutch oven bring 4 qt. water and 1 Tbsp. fine sea salt to boiling. Add pasta and cook 9 minutes. Carefully remove 1 cup of the pasta cooking water. Add shelled peas and snow peas to pot with pasta; cook 1 minute more or until al dente.

4. Drain pasta and peas; transfer immediately to the warm bowl. If pasta looks dry, add enough of the reserved cooking water to loosen it. Immediately pour the egg mixture over the pasta and sprinkle with flaky sea salt; toss well. Add mushrooms and toss. (The sauce should be creamy and silky. Add more pasta water as needed to loosen.) Top with additional Parmesan, additional ground black pepper, and, if using, chives and/or reserved mushrooms. Serve immediately. Serves 4.

Tips

A few things are very important to note here: working quickly once the pasta is drained, draining the pasta only briefly so that it stays mostly wet and doesn't dry out, reserving plenty of pasta water and using it as needed to loosen the sauce if the sauce dries out, and serving the pasta immediately.