Preheat the oven to 350 degrees fahrenheit
Add the flour, baking powder, baking soda and salt into a medium bowl. Stir with a fork to combine and set aside
In the base of a stand mixer or a medium mixing bowl with a hand mixer, add the sugar, lemon zest, and almond paste (we like to break it into pieces before adding to the stand mixer to help break it up). Mix on low for about 2 minutes until the almond paste is broken up into small pieces (about the size of a dime)
Add the the room temperature butter into the almond paste mixture and beat the mixture again on medium-high speed for 2 minutes until light and fluffy
Add in the eggs, vanilla, and almond extract. After adding, cream for 2 more minutes on medium-high speed until light and fluffy
Reduce the mixer speed to low and alternate adding the buttermilk and flour mixture, starting and ending with the dry ingredients. To do this, our preferred method is as follows: ⅓ of the dry ingredients, ½ of the buttermilk, ⅓ of the dry ingredients, ½ of the buttermilk, ⅓ of the dry ingredients (pulse after each addition). Note: do not over mix at this stage and just barely mix at each step to evenly combine the ingredients
Once the dry and wet ingredients are added and the batter is just combined, fold in the lemon zest and poppy seeds
Place the batter in a 9×9 inch glass pan lined with parchment paper and sprayed with cooking spray. Spread the batter into an even layer
Bake at 350 degrees for 35 minutes
While the cake is baking, make the poppy seed crumble (below)
After 35 minutes, top with crumb then bake for about 15-20 more minutes until or until a toothpick comes out clean
Set aside to cool
