First things first—preheat your oven to 350°F (175°C). This may seem like a no-brainer, but trust me, a properly preheated oven ensures that your bars bake evenly.
Grab an 8-inch square baking pan and line it with parchment paper. Leave some overhang on the sides for easy removal later. This will be your sweet launching pad for these delightful bars.
In a mixing bowl, blend together the cold diced butter, 1/4 cup of granulated sugar, and the pinch of salt. Using a pastry cutter or your fingertips, blend until the mixture resembles coarse crumbs. Add in 1 cup of flour and the baking powder. Mix until you form a soft dough. Once the dough is ready, press it evenly into the prepared pan. Bake this for about 13-15 minutes until it turns a light golden brown.
While the crust is baking, it's time to get the filling ready. In another bowl, beat together the eggs and the caster sugar until fluffy—this takes about 3 to 5 minutes. Add the freshly squeezed lemon juice, vanilla extract, lemon zest, and almond flour. Fold in the toasted shredded coconut gently. This step adds texture and that lovely coconut flavor.
Once the crust is done, take it out of the oven and pour the lemon coconut filling over the warm crust. Spread it out evenly. This will ensure every bite is as delightful as the last. Put it back in the oven.
Bake for another 20-25 minutes, or until the filling is set but still slightly jiggly in the center. Don't forget to keep an eye on it. If it starts to brown too much, you can tent it with some foil.
After baking, allow the bars to cool completely in the pan. Don’t rush this part! Once cooled, use the parchment overhang to lift the bars out. Dust with powdered sugar.