Prep the Baking Sheet by lining it with a silicone mat or parchment paper and preheat oven to 280°F (140°C).

Mix Dry Ingredients by pulsing together powdered sugar and almond flour in a food processor, then sift into a large bowl and whisk in poppy seeds.

Make Meringue by whipping aged egg whites until frothy, gradually adding granulated sugar and beating until stiff peaks form.

Combine Mixtures by gently folding meringue into dry ingredients until smooth and shiny.

Pipe Shells using a piping bag to create 1-inch disks on the baking sheet.

Rest & Bake the piped macarons for about 1 hour until they develop a skin, then bake for 15 minutes.

Cool them completely on the baking sheet after removal from the oven.

Prepare Filling by whisking together sugar, lemon juice, eggs, and cooking until thick. Add butter and fold in whipped cream.

Assemble by piping filling between two macaron shells to create sandwiches.