Slice the tempeh into 1 inch–wide and ¼ inch–thick squares.
Add ¾ cup water and the soy sauce to a pan that pairs with a steamer and bring the heat to medium.
Add the tempeh to the steamer that fits over the pan and steam for 15 minutes. If you don't own a steamer, just place the tempeh in the water and soy sauce.
Stir together 3 tablespoons flour, the salt, garlic granules, and black pepper.
Lightly dredge the steamed tempeh in the flour mixture.
Add the olive oil to a pan and bring the heat to medium.
Add the tempeh and cook each side for 4 minutes, then remove the tempeh from the pan.
Add the butter to the same pan and bring the heat to medium.
Add the shallots, garlic, and mushrooms and cook for 8 minutes.
Now, add the remaining 1 tablespoon flour and stir.
Add the Marsala wine, stir, and cook on medium for 5 minutes to cook off the alcohol.
Add the broth and stir frequently while it cooks and thickens for about 10 minutes.
Add the cooked tempeh and simmer for 15 minutes while you cook the pasta.
Bring a large pot of water to a boil.
Cook the pasta according to the package directions, and then drain.
Combine the pasta and the mushroom tempeh mixture, optionally top with thyme, and serve. If you are not serving immediately, you'll want to add more vegetable broth to loosen up the noodles.