Saute the minced garlic in the oil in a small saucepan over low heat. Allow to cook for a few minutes, until the garlic is tender and fragrant, but not browned.
Add the 1 cup of water to the saucepan, along with the cauliflower, and bring the water to a boil. (The water will not cover the cauliflower, and that's okay.) Once the water is boiling, lower the heat to a simmer and cover the pot to cook until the cauliflower is fork-tender and very soft, about 10 to 15 minutes.
Transfer the entire contents of the saucepan into a blender or food processor, and season with salt and pepper. Process until very smooth and creamy, with a texture similar to traditional cream sauce. (Always be careful when blending hot liquids-- the steam pressure can blow the lid off your blender. Cover the vent in your blender lid with a thin kitchen towel to allow venting.)
Season with additional salt and pepper, if desired, and serve hot over your favorite pasta.
Keep in mind that this sauce will need additional salt if served over plain pasta or steamed vegetables, as the flavor will get diluted. If you plan on adding another salt source, such as Parmesan cheese, the additional salt may not be necessary.