Preheat the oven to 425 degrees F. If using a pizza stone, heat the stone in the preheated oven for 10 minutes.
Heat a large nonstick skillet over medium-high heat. Lightly coat with cooking spray. Squeeze the sausages out of their casings into the skillet. Cook, breaking up with a wooden spoon, until cooked through. Transfer to a bowl lined with paper towel to absorb any oil. Set aside.
Heat the olive oil in the skillet and add the mushrooms. Cook until tender, 4 to 5 minutes. Season with salt and pepper. Stir in the garlic and oregano, and cook for 1 minute.
Place the naan on a pizza peel (or on a baking sheet if not using a pizza stone).
Spread ¼ cup tomato sauce on each naan, and divide the sausage, mushrooms and goat cheese evenly between the two naans.
If using a baking stone, transfer the pizzas from the peel to the stone in the oven. If using a baking sheet, transfer to the oven.
Bake until the cheese is starting to melt and the naan is golden brown, 7 to 8 minutes.
Transfer the pizzas to a cutting board and let rest for a few minutes before cutting.
Sprinkle the parsley over top. Slice the pizzas into quarters. Serve.