Melt butter over medium. Saute garlic in butter over medium heat for 1 minute. Add cauliflower, stock, and water and bring to a boil over high heat. Boil for 5 minutes and add potatoes. Boil for another 20-25 minutes, or until all vegetables are very soft (fork goes right through them). Blend with immersion blender or blend in batches in blender. Add fat free half and half and heavy cream and stir. Add cheeses and lower to low heat, stir until melted. Add nutmeg, taste and season with salt and pepper. I would make some homemade croutons and serve the soup with two floating on top.