Preheat oven to 350 degrees and cover a baking sheet with parchment paper.
Stir together the olive oil and garlic. Carefully slice the cauliflower into 1–1½" slices. The slices from the center will easily stay in one piece. Try to keep the outer slices whole as well. Brush both sides with garlic and oil mixture. Season both sides of the slices with salt. Place the cauliflower "steaks" on the parchment-lined pan with the best-looking side up. Sprinkle each piece with Parmesan cheese and red pepper flakes.
Bake for 40 minutes or until the center of the cauliflower is tender when pierced with a knife and the exterior is golden brown.
Serve nice and hot. Enjoy!
To ensure the best possible flavor, make sure to season both sides of the cauliflower steaks well!