Cook the macaroni according to the package instructions. Drain and set it aside.
Heat 1 tablespoon of olive oil in a pan and add the crumbled tempeh bacon. Cook for 5-10 minutes, until golden and crisp, then transfer to a plate and set aside.
In a large skillet or saucepan, heat the remaining 1 tablespoon olive oil over medium heat. Add the red onion and sauté for 4-5 minutes, until softened.
Stir in the garlic, potatoes, carrots, cauliflower, and cashews. Cook for 3-4 minutes, stirring occasionally.
Pour in the vegetable broth and add the garlic powder, onion powder, paprika, turmeric, salt, and pepper. Bring to a simmer and cook for 10-15 minutes, or until the vegetables are fork-tender.
Let the vegetable-cashew mixture cool a bit, then transfer to a blender. Add the nutritional yeast and Dijon mustard. Blend until smooth and creamy, adding 2-3 tablespoons water as needed to help the sauce blend and reach your desired consistency.
Pour the sauce over the cooked macaroni. Add half of the tempeh bacon and stir until everything is well combined.
Divide into bowls and top with the remaining tempeh bacon. Garnish with fresh parsley, if desired, and serve warm.