Prepare the Oven and Cake Pan: Preheat the oven to 350°F (175°C). Grease an 8-inch round cake pan with butter. Line the pan with two long strips of parchment paper arranged in a cross, allowing the ends to extend above the sides for easy lifting. Place a round piece of parchment paper over the bottom of the pan. Combine the Dry Ingredients: In a medium mixing bowl, whisk together the almond flour, baking powder, and kosher salt until evenly distributed. Set the mixture aside.
Cream the Butter and Sugar: Place the softened butter and granulated sugar in the bowl of a stand mixer fitted with the paddle attachment. Beat until the mixture becomes light and fluffy.
Prepare the Egg Mixture: In a small bowl, lightly beat the eggs with the vanilla extract and almond extract until combined.
Incorporate the Eggs: With the mixer running at a reduced speed, gradually pour the egg mixture into the creamed butter and sugar, adding it a little at a time. Increase the mixer speed once the eggs have been added, then continue beating until everything is thoroughly incorporated. Add the Almond Flour Mixture: Add the reserved dry ingredients to the wet mixture. Mix until the batter is smooth and evenly combined.
Fill the Cake Pan: Transfer the batter to the prepared cake pan and spread it evenly. Arrange the sliced pears over the surface, pressing each slice approximately halfway into the batter. Sprinkle the sliced almonds over the top, if using.
Bake the Cake: Place the pan in the preheated oven and bake for 55–60 minutes. The cake is ready when the center no longer jiggles and a toothpick inserted into the cake comes out clean. Around the 45-minute mark, check the top. If it is browning too quickly, loosely cover the cake with aluminum foil to prevent it from burning while the center finishes baking. Cool the Cake: Remove the cake from the oven and place the pan on a wire cooling rack. Allow the cake to cool completely in the pan before removing it, using the parchment paper overhang to help lift it out.
Finish and Serve: Transfer the cooled cake to a serving plate and dust the top with powdered sugar before slicing, if desired.