Brown the butter in a large skillet over medium high heat. Once it starts to get lightly brown, add the red pepper flakes and garlic and sauté for 30 seconds until fragrant and the butter is browned. Remove from heat and set aside.
Steam the cauliflower for 8-10 minutes, or until fork tender. Once tender, transfer the cauliflower to a high-powered blender. Add ½ cup of the cooking water and the red pepper and garlic brown butter mixture. Blend until smooth. If it’s still thick, stream in additional cauliflower water or milk, a few tablespoons at a time until smooth and thin. Taste and adjust salt and pepper as needed.
Cook the pasta according to the package directions. Drain and transfer back into the pot. Add the cauliflower sauce and toss to combine. Season with salt, pepper and parmesan and serve with fried sage. Enjoy!
To fry sage:
Heat oil in a small skillet over medium-high heat until hot.
Fry 6–8 sage leaves at a time until crisp, 2–3 seconds. Transfer with a fork to paper towels and sprinkle generously with coarse salt.