Prep the ingredients. Cut the cauliflower into small florets, peel and cube the potato, mince or crush the garlic, and shred the cheddar cheese.
Bring an inch or two of water to boil in a large pot with a steamer insert. Place the cauliflower and potatoes in the steamer insert, cover, and cook for 10 minutes.
While the veggies are steaming, melt the garlic in a non-stick frying pan on medium heat. Once the butter is hot and bubbling, add the garlic and 1 to 2 small strands of rosemary or 4 to 5 strands of thyme. Cook for about 10 minutes, adjusting the heat when necessary so the garlic doesn’t get crispy or burnt. Swirl the pan often. Take off the heat and cool a little before pulling the rosemary or thyme out, making sure to get the garlic and butter off of them.
Pour the butter and garlic into a blender along with 1 tablespoon heavy cream. Spoon the steamed cauliflower and potatoes into the blender along with the cheddar cheese. Cover and blend on a low or medium setting (I use the 3 on a Vitamix). If your blender comes with a tamper, use it to press the mixture down on the blades. Blend until there aren’t anymore chunks.
Pour into a serving dish and then add salt and pepper to taste.
If you decide to use rosemary, stick to 1 or 2 strands. Anything more than that and the rosemary flavor can be overpowering.
If you have a really powerful blender, like a Vitamix, don’t blend on the really high settings-the end result is more soup-like than mash.
If you don’t have a blender, you can use a food processor. Or you can pour everything in a bowl and mix with an electric beater. If using an electric beater, the cauliflower chunks might be harder to get rid of, so steam the cauliflower and potatoes longer to make it easier.