1. Preheat oven to 350 degrees. Butter and line a loaf or 9-inch round pan with parchment.
2. Mix butter and brown sugar together and spread evenly over bottom of pan.
3. Peel and core pineapple, cut in half, and slice into thin, even half rounds. Arrange on bottom of pan, making sure to cover entire surface. (Gebhart fans them, slightly overlapped, in pan.) Next, sprinkle well-drained and thawed frozen cherries, or spread a cooked cherry compote on top of the pineapple.
4. In a stand mixer, combine sugar, flours, baking powder, and salt on low speed. Add butter and increase speed to medium for 5 minutes. After butter is well incorporated, add eggs 1 at a time. Scrape sides of bowl and add heavy cream, vanilla, chopped rosemary, and orange zest until incorporated.
5. Carefully spoon batter into pan and place in oven. Bake for 25 to 30 minutes, or until a tester comes out clean. Rotate halfway through.
6. Let cool until slightly warm to the touch, then run a small offset spatula or butter knife around the edges and turn out onto a serving platter.