1. Preheat oven to 325 degrees. Butter a 5-by-10-by-2 1/2-inch loaf pan, and line with parchment paper. Butter lining; dust with all-purpose flour, tapping out excess.

2. Whisk together both flours, baking powder, and salt; set aside. Put butter and sugar in the bowl of an electric mixer fitted with the paddle attachment; cream on medium speed until smooth. Add eggs, one at a time; mix until smooth. Mix in extracts. With mixer on low speed, mix in reserved flour mixture in three additions, alternating with two additions of milk; mix until smooth.

3. Pour batter into prepared pan. Bake until a cake tester inserted into center comes out clean, about 1 hour. Transfer cake in pan to a wire rack. Poke holes all over top of cake with a wooden skewer. Pour liqueur on top; let cool completely.

4. Invert cake to unmold; peel off parchment, and reinvert. Just before serving, cut cake into 3/4-inch slices, and top with flambeed pineapple and sauce.