Trim the green leaves off the bottom of the cauliflower, keeping the core intact. Cut two thick, 1.5-inch (4cm) cross-section slices from the middle of each head.

In a small bowl, mix the smoked paprika, garlic powder, cracked black pepper, and kosher salt. In a separate wide dish, toss the panko breadcrumbs and grated parmesan cheese.

Preheat your oven to 425°F (220°C). Whisk the olive oil and Dijon mustard together, and brush generously over both sides and edges of the steaks. Press the edges into the panko mixture, then sprinkle the coarse spice blend heavily over the flat tops.

Place crinkled parchment paper onto a dark metallic baking sheet. Arrange the steaks and roast for 25-30 minutes, flipping carefully halfway through, until the center is tender and the edges are deeply caramelized.

While roasting, whisk together the mayonnaise, minced garlic, lemon juice, and turmeric until a smooth, pale yellow sauce forms.

Once out of the oven, zigzag a thick drizzle of the creamy garlic sauce over the top of the steaks. Garnish generously with freshly chopped green parsley and red pepper flakes before serving.