Place a rack in the center of the oven and heat to 385°F.

Cut the cauliflower into medium florets, then cut the florets into thick slices. (They will vary in size, but the idea is to create some flat surfaces that will rest on the pan and caramelize nicely.) Toss the florets with 2 to 3 tablespoons olive oil, a few big pinches of salt, and several grinds of pepper. Spread them, flat sides down, on a heavy baking sheet. Bake for 20 to 30 minutes, or until they are tender and golden brown. Transfer the pieces to a plate and set aside.

Meanwhile, trim the Belgian endive and separate it into leaves. Rub the leaves with another tablespoon or so of the olive oil to coat the surfaces. Sprinkle lightly with salt. Place the leaves on the baking sheet that you used for the cauliflower and roast for 5 minutes, or until the leaves are slightly softened and just barely brown around the edges. Remove from the oven. Sprinkle the leaves with the lemon zest, lemon juice, and vinegar. Cover with foil to keep warm.

To finish, heat a sauté pan over medium-high heat with the butter and chicken stock. Add the cauliflower pieces and cook, tossing to distribute the butter and stock, until the pan is dry.

To finish, sprinkle the fresh mint over the endive leaves. Put the cauliflower into a shallow bowl and tuck the endive leaves onto and around it. Serve immediately.