Preheat the oven to 400F. Lightly grease a 2 quart (11x7 or similarly-sized) casserole dish and set aside.
To make the cauliflower Alfredo sauce, heat the cooking oil in a large pot over medium-high heat. Once melted, add onions and garlic. Cook, stirring occasionally, until onions are translucent, about 5 minutes. Add cauliflower florets and saute for another 2-3 minutes. Once slightly tender, add vegetable broth, cover and cook until cauliflower is soft all the way through, about 5 more minutes. Transfer to a high-speed blender and add remaining Alfredo Sauce ingredients. Blend until completely smooth. Set aside.
Peel and slice the potatoes into slices between ⅛"-¼" big. In a sauté pan, heat up the oil. Sauté the onions for 5-7 minutes until they are translucent and fragrant. Add the minced garlic and sauté for an additional 60 seconds. Remove from heat.
Assemble the scalloped potatoes by placing half of the potatoes into an even layer at the bottom of the casserole dish. Top with ½ of the Cauliflower Alfredo sauce. Evenly spread the onions over the Alfredo sauce. Top with the remaining potatoes and Alfredo sauce. Cover in tin foil and bake for 20 minutes. After 20 minutes, remove tin foil, and continue to bake for an additional 20 minutes until the potatoes are tender and the sauce is boiling up around the sides.
Remove from the oven and top with vegan parmesan cheese (optional) and fresh chives. Serve warm.
Serving and Storing - Serve these potatoes with vegan parmesan cheese, freshly ground pepper, and fresh chives. Serve as part of your holiday meal or with homemade vegan soup. Store leftovers in an airtight container in the refrigerator for up to 3 days. To reheat, cover with tin foil and gently reheat in the oven at 350F
Recipe Tip - Consider making a whole batch of creamy cauliflower sauce and stored the extra in the freezer for up to 2 months. This makes the perfect skinny alfredo sauce for a quick and easy meal.
Calories: 184kcal | Carbohydrates: 30g | Protein: 7g | Fat: 2g | Saturated Fat: 1g | Monounsaturated Fat: 1g | Sodium: 9mg | Potassium: 665mg | Fiber: 4g | Sugar: 2g | Vitamin A: 15IU | Vitamin C: 11mg | Calcium: 27mg | Iron: 1mg