Heat 2 tablespoons olive oil in a large skillet over medium-high heat. Add 1 pound mushrooms (sliced) and cook for 8 to 10 minutes, until they release their water and start to turn golden. Stir from time to time. Season with ¾ teaspoon salt and black pepper.
Lower the heat to medium. Add a drizzle more olive oil if needed, 1 onion (chopped) and cook for about 3 minutes, until soft. Stir so it doesn’t stick. Add 1 - 2 cloves garlic (grated) and cook for 30 seconds, just until fragrant.
While the mushrooms cook, whisk together 2 cups vegetable broth, 3 tablespoons all-purpose flour, 1 tablespoon mustard, 1 tablespoon Worcestershire sauce, 2 teaspoons smoked paprika, and 1 teaspoon dried thyme in a bowl or measuring jug. Whisk until smooth so there are no lumps.
Pour the sauce into the skillet and stir right away. Add 1 can black beans (rinsed) and mix well. Let it simmer until thick and creamy. If it gets too thick, add a splash of broth or water.
Turn off the heat. Stir in ½ cup Greek yogurt and 2 tablespoons fresh parsley (chopped) until smooth. Taste and adjust salt and pepper. Serve warm with rice, noodles, mashed potatoes, or crusty bread. Add parmesan if you like.
