Heat 2 tablespoons olive oil in a Dutch oven or large pot over medium heat until shimmering. Add 1 diced medium yellow onion, 6 to 8 ounces sliced mushrooms, and ½ teaspoon of the kosher salt. Cook, stirring occasionally, until the onion is tender and the mushrooms start to brown, about 8 minutes. Meanwhile, bring a large pot of heavy salted water to a boil over medium-high heat.

Stir in 1 tablespoon minced garlic and cook until fragrant, about 30 seconds. Add 1 pound lean ground beef and the remaining 1 teaspoon kosher salt. Cook, breaking it up into small pieces and stirring occasionally, until cooked through and browned, 7 to 8 minutes.

Increase the heat to medium-high. Stir in 1 pound diced beefsteak tomatoes and cook, stirring occasionally, until the tomatoes soften and release their juices, about 4 minutes. Stir in 1 (24-ounce) jar Prego Traditional Italian sauce and 1 tablespoon granulated sugar and bring to a simmer. Reduce the heat as needed to maintain a simmer and cook until the flavors meld, about 15 minutes.

Meanwhile, add 1 pound dried spaghetti to the boiling water and cook according to package directions until al dente. Drain the pasta.

Add the pasta to the sauce and toss until the pasta is evenly coated. Taste and season with more kosher salt as needed. Garnish with finely chopped fresh parsley leaves if desired and serve with grated Parmesan cheese.