Preheat the oven to 325 degrees F. Butter two 9-inch-round cake pans and line the bottoms with parchment paper. Butter the parchment and dust with flour, tapping out the excess.
Whisk the flour, baking powder and salt in a large bowl. Beat the butter in a separate large bowl with a mixer on medium-high speed until creamy, about 2 minutes. Gradually beat in the granulated sugar until light and fluffy, about 4 minutes. Add the eggs one at a time, beating until incorporated, then add the vanilla and almond extracts. Reduce the mixer speed to low and add the flour mixture in 3 batches, alternating with the milk; beat until just smooth, 2 minutes.
Divide the batter between the prepared pans and sprinkle each with 1 cup blueberries. Bake until lightly golden and a toothpick inserted into the centers comes out clean, 25 to 30 minutes. Let cool 10 minutes in the pans on a rack, then invert the cakes onto the rack to cool completely.
Meanwhile, spread the almonds on a baking sheet and bake until lightly golden, about 10 minutes; set aside. Beat the heavy cream and 2 tablespoons confectioners' sugar in a large bowl with a mixer on medium-high speed until stiff peaks form, 2 to 3 minutes. Gently fold in the lemon curd, leaving some yellow streaks. Spread the cream mixture over 1 layer of cake almost to the edge. Place the second cake layer on top and gently press; refrigerate at least 1 hour or overnight.
Before serving, whisk the remaining 1 cup confectioners' sugar with the lemon juice in a medium bowl until it forms a smooth glaze. (Add 1 or 2 drops of water if it's too thick.) Pour the glaze over the center of the cake and spread with a spatula or spoon to the edge, allowing some to drip down the sides. Sprinkle with the toasted almonds.