Ready In: 2 hrs
Prep: 1 hr 10 mins
Cook: 40 mins
Yields: 10 Servings
Combine sirloin and 1 tablespoon of the soy sauce and stir until combined; refrigerate for 1 hour.
Bring a large pot of salted water to a boil and cook pasta for 15 minutes or until al dente. Drain, reserving 1 cup pasta water and set aside.
Dry sirloin with paper towels and sprinkle with pepper. Heat 1 tablespoon of the oil in a large skillet over medium-high heat. Add beef to skillet and cook, stirring occasionally, for about 8 minutes or until browned on all sides; remove beef from skillet using a slotted spoon and set aside.
Heat remaining 1 tablespoon oil in skillet. Add onion and mushrooms to skillet and sprinkle with salt. Cover and cook about 7 minutes, stirring occasionally, or until softened. Remove cover and cook an additional 1 minute or until most of the liquid in the pan has evaporated.
Stir tomato paste into mushroom mixture and cook 1 minute. Sprinkle flour into pan and cook, stirring constantly, for 1 minute. Stir in broths and bring to a boil. Reduce heat to medium and simmer sauce for 4 minutes or until thickened. Stir in reserved beef and any accumulated juices and remove from heat; let cool 10 minutes.
Stir remaining 2 teaspoons soy sauce, arugula and yogurt into skillet until well blended. Stir in rigatoni until well blended; add pasta water by the 1/4-cupful if needed to loosen sauce.