1. In a small saucepan, bring 1/2 cup of water to a boil. Remove from the heat, add the poppy seeds and cover. Let stand for 1 hour. Scrape the seeds into a blender and pulse until lightly crushed.
2. Preheat the oven to 350°. Lightly grease and flour an 8-inch square baking pan, tapping out any excess flour. In a medium bowl, whisk the 1 1/3 cups of flour with the baking powder and salt. In a large bowl, using a handheld mixer, beat the butter with the granulated sugar at medium-high speed until fluffy, about 3 minutes. Add the poppy seed mixture and beat at medium speed until just combined. Add the eggs to the batter one at a time, beating well between additions. Beat in the vanilla and almond extracts. Using a wooden spoon, stir in the flour mixture until just incorporated. Scrape the batter into the prepared pan.
3. Bake the cake for about 45 minutes, until the top is golden and a toothpick inserted into the center comes out clean. Let the cake cool in the pan for 10 minutes, then invert it onto a wire rack and let cool completely, about 2 hours. Dust the cake with confectioners' sugar, cut into squares and serve.