Roasting fruit intensifies its sweetness and flavor, and pineapple lends itself to this technique especially well. In this recipe, the fruit makes its own sauce as it cooks. The subtle fragrances of vanilla and cardamom add depth of flavor.
Serve the pineapple and its sauce over ice cream, atop pound cake, or simply garnished with a dollop of rum-spiked mascarpone.
Position a rack in the middle of the oven, and preheat to 375 degrees F.
Cut the pineapple in half lengthwise, then cut each half lengthwise into 1-inch-thick spears (you should have 8 spears). Remove and discard the core from each spear. Transfer the pineapple spears to a glass baking dish that's large enough to accommodate the fruit in a single layer.
Place the sugar, vanilla, cardamom, pineapple juice and melted butter in a small bowl and stir to blend. Top the pineapple with the sugar mixture. Roast for 15 minutes, then baste the pineapple with the juices in the pan. Turn the spears over and continue roasting until the fruit is tender and the sauce has thickened slightly, 20 to 30 minutes more, basting once during this period. Cut each spear crosswise into 1/2-inch-thick slices and serve with the sauce.