Cook the Pasta: Bring a large pot of salted water to a boil. Add fettuccine pasta and cook according to package instructions until al dente, about 8-10 minutes. Reserve one cup of pasta water before draining.

Prepare the Lentils: In a separate pot, combine green lentils with water and bring to a boil. Simmer for 15-20 minutes until tender but not mushy. Drain the lentils.

Sauté the Onions: In a skillet, heat olive oil over medium heat. Add diced onion and sauté for about 5 minutes until translucent.

Add Garlic and Mushrooms: Add minced garlic and sliced mushrooms. Cook for 8-10 minutes until mushrooms turn golden brown.

Season the Mixture: Stir in soy sauce, smoked paprika, and dried thyme. Cook for about 2 minutes to enhance flavor.

Create the Sauce: Pour in vegetable broth and simmer for about 5 minutes until flavors meld and sauce thickens.

Combine Lentils and Yogurt: Reduce heat to low, stir in cooked lentils and fold in yogurt off the heat to prevent curdling.

Final Seasoning: Adjust seasoning with salt and pepper. Add reserved pasta water if the sauce is too thick.

Serve and Garnish: Serve stroganoff over cooked fettuccine and sprinkle with chopped parsley before serving.