Prep the beef: Pat the sliced beef dry with paper towels. Season with 1/2 teaspoon salt and 1/2 teaspoon black pepper. This helps it sear rather than steam.

Cook the pasta: Bring a large pot of salted water to a boil. Cook the whole-wheat pasta until just al dente. Reserve 1/2 cup of pasta water, then drain and set aside.

Sear the beef: Heat 1 tablespoon oil in a large skillet over medium-high. Add the beef in a single layer (work in batches). Sear 1–2 minutes per side until browned but still slightly pink inside. Transfer to a plate and cover loosely.

Sauté the veg: Lower heat to medium, add remaining oil. Add onions and mushrooms with a pinch of salt. Cook 6–8 minutes, stirring, until mushrooms release liquid and brown and the onions soften. Add garlic and cook 30 seconds until fragrant.

Build the sauce base: Sprinkle flour over the mushroom mixture and stir for 30–60 seconds. Whisk in the broth gradually to prevent lumps. Add Worcestershire, Dijon, and smoked paprika if using. Simmer 3–4 minutes until slightly thickened.

Temper the yogurt: In a small bowl, whisk Greek yogurt with a few tablespoons of the hot sauce to warm it up. Then stir the tempered yogurt into the skillet over low heat. Keep the sauce below a simmer to prevent curdling.

Return the beef: Add the seared beef (and any juices) back to the pan. Stir gently and cook 1–2 minutes to warm through. Adjust thickness with a splash of reserved pasta water if needed.

Combine with pasta: Add the drained pasta and toss until coated. Season with more salt and pepper to taste. Add lemon juice if you want extra brightness.

Finish and serve: Sprinkle with chopped parsley and a pinch of red pepper flakes if you like heat. Serve hot with a simple green salad on the side.