Step 1

Preheat oven to 425°F.

Step 2

In a large bowl, whisk together the tomato paste, olive oil, and Dijon mustard. Note that the olive oil will not fully incorporate. That’s ok. Add 1/4 cup of the Parmesan cheese, the oregano, garlic powder, salt, and pepper.

Step 3

Break the head of cauliflower into florets and add them to the tomato paste mixture. Stir using a spatula to make sure the sauce is getting onto the cauliflower, which should end up stained red. Use the spatula to transfer all the cauliflower and sauce to a large baking sheet.

Step 4

Roast until darkened in spots and is tender-crisp when stuck with a fork, 20-25 minutes. Stir gently with a metal spatula and, if desired, sprinkle with more Parmesan cheese to serve.