In a large bowl, soak udon noodles in boiling water for about 30 seconds or just until loosened. Strain and set aside.
Heat a large pan on medium heat, fry bacon until cooked and slightly browned on the edges, about 4-5 minutes. Transfer the cooked bacon to a plate, draining off any excess grease. Leave about 1 teaspoon of bacon grease in the pan and discard the rest.
Sauté garlic and onions until slightly softened, about 1 minute. Add chopped tomatoes and fry until softened, about 2-3 minutes.
Add marinara sauce and heavy cream and mix until combined. Let the sauce naturally come to a boil on medium heat to slightly thicken.
Add udon and bacon; toss to coat evenly. Transfer to a large serving plate.
Garnish with Parmigiano and dried parsley as needed. Season to taste with salt and pepper. Enjoy!
